My car's interior smells slightly of gear oil and it seems to be coming through the leather shift boot. If you take off the gear knob and pull up the leather boot and smell the hole, you can smell the gear oil. I've changed my transmission oil twice and both times made sure to only refill it by 1.8 quarts. Any idea about the cause?

hmm, after i changed my tranny oil my car interior smelled like gear oil for a few weeks. it's fine now though. although im not positive since i haven't driven in a while. curious here too.

Uh, under the leather boot there's a rubber boot right? It should seal around the shift lever.

Its odd that this should come up.
I have the same issue, but only in relatively hard left turns.
The smell is definitely tranny lube and it is coming through the shifter.
I've checked the rubber boot and such and there is absolutely no leak - of air or oil.

This started immediately after changing my tranny lube last summer and it persists.

When I started poking around a few month ago to solve this, I drained the oil out and refilled it, metering the exact amount of indicated oil and through the fill port (normally, I'd pour the oil down the shift turret).
That made no difference. Adding a layer of gasket compound to the base of the sealing boot inside the shifter did nothing as well.

I only smell it on left turns - especially at high speeds.

I'm stumped.

I have also noticed the smell ever since i first changed out my tranny fluid with red line....first i thought i had overfilled (which i may have), but never took off the leather shift boot to find where the smell was coming from. Recently I changed to RP and filled the tranny with less fluid, but the smell of RP is still faintly there. When I get the AF short shifter, Ill have to take a look...

ok so i went investigating today. took the rubber boot covers off and noticed oil under it. i'm not positive, but i didn't remember finding oil there before i changed my tranny fluid. wondering is the oil spooling up more so now. looked to see if i had any part that would let air or oil out, but i don't see anywhere that would prove to be a problem.

so here's a question. did any of you add the gear oil through the shifter at one time or another?

so here's a question. did any of you add the gear oil through the shifter at one time or another?Read the middle of post #4.

yea i read that you did. wondering if everyone else having this oil smell did so as well. maybe a reason, possibly?

yea i read that you did. wondering if everyone else having this oil smell did so as well. maybe a reason, possibly?

both times i changed my tranny fluid was under the car. There was a hole in my shift boot at one time and oil was leaking into the leather boot...i had mazda patch the hole and replace the shift boot...who knows if they really did a good job on patching the hole or not.

I had the exact same problem with my car and I did two things to make the best effort at solving the problem. First, I removed the rubber inner shifter boot and applied a bit of red tacky spray gasket sealer to the seal after cleaning the body where the gasket secures. Second, since I swapped the factory clutch back in for a while, I had a chance to make sure that the vent was clean. I can't remember particulars on the vent matter, but both seem to have solved the problem and my interior once again smells like new leather.

Where is the vent?

MM, I looked at the cd service manual to refresh my memory but a vent wasn't illustrated nor listed. Although there is a vent for the bellhousing/clutch ass'y heat, I am wondering if I might be thinking of that '85 RX-7 that I repaired last spring. However, I seem to remember thinking it strange that there would be a vent of some kind in the bellhousing area for gear case fumes(?) whichever transmission I am thinking of. Might I be mistaken regarding the 8's trans? I looked at both the R-15 and Y-16 diagrams. I would imagine that there has to be a vent or else the seals would be stressed every time the transmission warmed up. Maybe I should not have mentioned it with so few details in my memory.....sorry.

No, I'm sure there must be a vent somewhere.
I just haven't spotted it since I've never had the tranny out from under the car (I just push it out of the way on swaps).
As you mention, it isn't noted in the manual.
If you can think where it might be exactly, I'll go poking around.

I tend to think that it was near the top-center of the case in the bellhousing side, but at the same time that seems ridiculous to me. More likely, it would be in the same area on the outside of the case. The reason I am thinking all of this is because I cleaned the clutch disc dust out from the bellhousing and in doing so saw the vent. Then I realized that what might have been causing the smell was the RP fluid clinging to the vent area(or some stupid theory like that) and causing the odor. Whatever the objective truth was/is, when I did both the things I mentioned above, a day or two later the odor was gone. Of course, I am the forum's seeming King of changing more than one thing at a time and then making the mental work more difficult for myself to figure out what really happened. Another one of those "can't hurt to do it" ideas that came along while I was concentrating on something else. That's how I temporarily messed up my nitrous operation for a while but at least we now know just how sensitive the MAF is.....

Of course, I am the forum's seeming King of changing more than one thing at a time and then making the mental work more difficult for myself to figure out what really happened. Then, I'm afraid I might be the Crown Prince of too many variables.
Do I really need to kneel?

MazdaManiac: "Oh look! Bright, shiny objects!"
[[sound and smell of important stuff, burning]]

i will look at the spare i have sunday when i get home. photos will follow if i can find it..

beers :beer:

Thanks, Bro. I think the vent we are looking for will be at the front and top of the transmission case, somewhere.

You guys are awesome. I love having rx8club as a resource.

Thanks, Lion. I have another thought that I want to run past you guys but it is only speculative since I haven't yet opened up the RX-8 transmission to see if what I suspect might be true. Wanna hear it?

Spit it out. I want to hear so MazdaManiac will stop talking about it every time I see him,,JK
I would like to hear anything on this.

The OEM manufacturers are using thinner and thinner lubes to help increase fuel economy whether in the engines, transmissions, or differentials. As such, and this is where I theorize, the manner in which the lubes are delivered to the friction zones have to be engineered in a different way than they used to be. In the transmissions, when the fluids were heavier or of the clinging variety from the factory the interior of the transmission case was not a big deal because the lube easily stuck to the gear and synchro faces. Now, with the fluids rinsing off the gears/synchros quicker, the factory has to design faces and channels inside the gear case that helps hold the fluids where they need to be in order to assure proper lubrication. If we switch our fluids to the clinging types like RP and RL the fluids and channels are working together in a way that never allows the fluid to leave the gear faces except by force from the fluid pumping around. In other words, I think there may be over-collection of the fluid in the vent area due to lack of circulation and that is causing either a little bit of fluid to huff out the vent or more vapors than expected are huffing out the vent and into the car. Again, this is only speculation and it is based on my memory of cleaning the vent, sealing the inner boot, and swapping back to factory-type fluids, that led to elimination of that icky odor in my interior.

The vent is to the right and around 6 inches forward of the shifter.

Spit it out. I want to hear so MazdaManiac will stop talking about it every time I see him,,JKDo I repeat myself? Must be getting old...

The vent is to the right and around 6 inches forward of the shifter.
I'm about to jack the car up for an oil change (PukerBowl is boring - except Prince), so I'll poke the scope in there.

Spit it out. I want to hear so MazdaManiac will stop talking about it every time I see him,,JK
Do I repeat myself? Must be getting old...

The OEM manufacturers ...odor in my interior.Well thought theory, but I don't think there is any significant difference between the Y16 in my Miata and the one in my '8 - and the one in the Miata doesn't smell, even though I use the same Redline mix in both.

Spit it out. I want to hear so MazdaManiac will stop talking about it every time I see him,,JK
Do I repeat myself? Must be getting old...

Would be nice to get our hands on Swoope's extra tranny and pull it apart......I have some other ideas about how to make it stronger and would love a peek inside.

Would be nice to get our hands on Swoope's extra tranny and pull it apart......I have some other ideas about how to make it stronger and would love a peek inside.


move to lakeland, it will set you free. and hogcar wins...

you can see the scale and the pen i pointing to what would be my guess is the vent... i can lift it up and spin it...

i wonder if you fill through the shifter it drifts over, or an over fill spits oil....


beers :beer:

i wonder if you fill through the shifter it drifts over, or an over fill spits oil....Well, that's part of the mystery - I've got no leakage at all. The entire tranny is completely dry on the outside. Spotless.
So is the turret.

how many people smelling this have an uninsulated aftermarket cat/mid pipe?

how many people smelling this have an uninsulated aftermarket cat/mid pipe?

i think i qualify as not insulated aftermarket cat... and no problem... trans oil was changed at 30k miles with rp... as was the diff...

was done by the dealer while they were replacing my mop...

beers :beer:

What happened to the MOP?
I think mine is sticking open after hard runs.

What happened to the MOP?
I think mine is sticking open after hard runs.

had a cel, at 18 k miles... they replaced the o2 sensor. then at 30 k miles. with lots of imput the mop was replaced... car never ran bad. but bad stuff happened after...

pm me for the rest of the story...

beers :beer:

I went to Redline 75W140NS gear oil after the second trans failure, partly because I know my trans is getting much hotter now due to the radiated heat from my exhaust which I know for a fact glows bright cherry red under various throttle conditions (melted the rear O2 wiring connector solid :Eyecrazy: ) and comes a bit closer to the trans due to the straighter run. I never got the gear oil smell until I made that oil change, and I didn't fill it through the shifter because if you ever spill gear oil in the interior you'll never get rid of that smell.

I went to Redline 75W140NS gear oil after the second trans failure, partly because I know my trans is getting much hotter now due to the radiated heat from my exhaust which I know for a fact glows bright cherry red under various throttle conditions (melted the rear O2 wiring connector solid :Eyecrazy: ) and comes a bit closer to the trans due to the straighter run. I never got the gear oil smell until I made that oil change, and I didn't fill it through the shifter because if you ever spill gear oil in the interior you'll never get rid of that smell.Must be running some monster EGTs. My midpipe doesn't reach those kinds of temps.

The technique for the gear oil requires a few feet of nitrile tubing and a funnel.
Chance of getting gear oil inside the car is nil.
I have a magic potion for oil spills, just in case.

ok, I thought you were just pouring it in the hole :uhh:

I have a full factory exhaust system and have only filled the tranny from underneath the car. I might have gone maybe a tenth of a quart over on this latest fill, but that's the only reason I can thing of.

The dealer (of course) says they can't smell it. I'm going to try sealing the rubber boot this weekend and seeing if that helps.

how many people smelling this have an uninsulated aftermarket cat/mid pipe?

I got it at the track day I did with stock cat.... Never had a problem on the street or autocrossing.

I got the oil smell too after my second trans oil change. No leaks at all, not even any residue. It's absolutely clean and yet, the light smell.
Am I a car geek if I like it?

I got it after I added Pre mix.

Had it for 3 tank fulls, then it went away.

Are you sure its not premix?

gear oil and exhaust oil are two entirely different smells

Even though I was entirely sure it was gear oil, I still stuck some up my nose to be sure (for comparison).


Am I a car geek if I like it?
Yes. Yes, you are.
Actually, if I know that it isn't something immanently failing, I don't mind it either.
The wife has a different opinion...

I got it after I added Pre mix.

Had it for 3 tank fulls, then it went away.

Are you sure its not premix?It's not premix. I don't premix (yet - waiting to hear what olddragger finds out from the lab) and I have the smell. Like a lot of folks, the smell started after my first tranny fluid change last June.

Hopefully someone figures out how to get rid of it 'cause I can't stand the smell. :wallbash:

I just noticed the smell after my RP tranny change, but it was probably the most noticable after about 4-5 days of NOT driving the car b/c of winter weather...??? I went to get something out of the car after it had been sitting for 5 days and the smell was very noticable??

I'm reviving this old thread. I just changed the transmission fluid to RP75W90 and now my cabin smells like a giant natural gas leak!! I thought maybe it'll go away after a week, but it's actually getting stronger. Kind of iffy if you think about it cause we've been breathing in the odorless OEM transmission fluid all this time unknowningly. :mdrmed:

Why can't aftermarket gear oil be odorless like the OEM fill?!

OEM oil stinks, too.

I don't know why this is happening and I am stumped.

I checked every seal on the tranny (front, rear, turret and all of the sensors) and I can't find oil anywhere.
Does any manufacturer make a dye that would be benign to the transmission internals that I can add to the oil for a couple of weeks?

Yes, on the dye. We use it in the OEM and, with an ultraviolet/black light we see where the leaks are. I'll look into that and see where I can direct you to buy some. Even better, if we have some laying around I'll send it to you. In the meantime, try "apexdyes.com".

The only thing I can think of is my OEM fluid fill was a little low. Maybe they underfilled it on purpose.

Do people with the Miata have the same problem?

Same problem here. Been almost 3 weeks now. The smell seems to be dying down though. Only a very faint smell now. I'll give it more time before I tear down the center console.

FS

if you want the rid the smell forever guys buy new cabin air filters.

if you want the rid the smell forever guys buy new cabin air filters.

You've obviously never worked with tranny fluid :)

Yeah, the smell is not coming through the HVAC and a "filter" cannot ameliorate the smell of petroleum products.

The cabin air filter is basically good for french fries and farts.

Same problem for me, too. The dealer changed the oil to RP at my 30k checkup and the smell was immediately apparent after the change. I figured it would go away, but about 3k or so miles later, it's still there.

~ Matt

So the question I have is, should I actually change oil over to RP if I am going to get this smell? I'm trying to gauge what percentage of people who have changed get this smell, and if they are doing anything different.

I would love to with the RP gear oil in that I already have, but not if its going to make my DD stink.

the smell gets stronger for me if i have the moonroof open and/or the A/C on "fresh..."

Same problem for me too. It started after the 30k checkup. My mechanic said he's had this problem in several other 8's, but doesn't know how to solve the problem. It seems to be coming from around the shifter.

For me there's definitely residue that's in my shift boot. I'm thinking about replacing my shift boot and seeing if that cures it.

here is the deal...

i changed mine sat. no spills except the little dribble that says its full....

i have put ~600 miles on it since... i am getting just a bit of gear oil smell if the windows are down at a stop...

gear oil is just that strong it will take a while to go away... royal purple or reg the smell is the same..

beers :beer:

I noticed that the smell gets worse as the tranny warms up. Here in MI the temps have been in the 'teens and 20s for the most part and I get the smell when I get on the freeway for a while but not before. I never really had any gripes with the factory fluid but I guess I'll next try the BG Synchroshift II and if that doesn't show definite benefits, I'll probably go back to the stock stuff.

WHERE THE HELL IS IT VENTING!?!

It really is driving me nuts. I can't figure it out.
It definitely seems to enter the cabin through the shifter area. On my car, it matters not if any windows are open or the ventilation is running in any mode.
It is more pronounced when it all gets hot, but the sweeping turns seem to really make it vent.

OEM oil stinks. Maybe not as much as the Redline, but it is NOT just an increased smell of the oil itself that is causing this.

I noticed that the smell gets worse as the tranny warms up. Here in MI the temps have been in the 'teens and 20s for the most part and I get the smell when I get on the freeway for a while but not before. I never really had any gripes with the factory fluid but I guess I'll next try the BG Synchroshift II and if that doesn't show definite benefits, I'll probably go back to the stock stuff.

Let me know what you think, but I have been very pleased.

i must say that, I too, have the smell sometimes while idling/sitting still. I think this is just inherent in the car when the trans vent is sitting very close to the shifter boot.

dude...i juss got my fluid changed and my car smells!!

my girlfriend was comin in my car and as soon as she opened my car door she was like, "WHATS THAT SMELL?!?! IT SMELLS FREAKNG NASTY"

hahah i do have to say that the smell is quite bad tho:(

I think the question is how do we seal up the MF so it is airtight between the cabin and the transmission. One poster in another thread said he used caulking around the rubber boot to take care of the problem.

I used hairspray last time, which did well, but next time I'll use red head gasket sealer/spray. Pretty tacky stuff that dries quickly. I don't know if that solves the problem but good sealing can't hurt.

Is it at all possible that the majority of us who are having this problem have, somehow, over-tightened the bolts that hold the plate to the rubber inner boot?

Question....Those people who have the problem and want to try a costly experiment, what happens if you change your transmision oil again but this time using OEM transmission oil? Does the smell go away?

Andrew

Take a look at post #58.

I think a poll should be started with options such as:

Yes it smells:
a) I poured it in through the shifter (even once)
b) I always use the fill plug and have never removed the shifter
c) I've replaced my shifter with a short throw
No it doesn't smell:
a) I poured it in through the shifter (even once)
b) I always use the fill plug and have never removed the shifter
c) I've replaced my shifter with a short throw

Eliminate one or some of the possibilities such as having popped out the shifter.

Mine smells -> Used drain/fill bolt, stock shifter, never opened up console before.

Well shizzle my nizzle then.

Take a look at post #58.
I didnt read it that way but I am guessing you are saying you have changed back to OEM Fluid and still have the probolem?

Here is my experience:

1st time transmission fluid changed, I did not have the smell. This applied:
b) I always use the fill plug and have never removed the shifter.

Now that I removed the shifter for flywheel install, the smell is around.

The difference from my 2 changes, was that the 2nd time i reused the crush washers on both fill/drain plugs. However, I believe the smell is slowly going away, or just very faint/noticible when a vent is open.

Goodbye!
Edgardo

Both times it was through the fill and drain plugs and both times I had fresh washers installed. There was no smell after the first time with Redline, but the second time with Royal Purple there was a smell. I put in 1.8 quarts the first time, but the second time it was more like 1.9.

i just took a bit of castoil super degreaser to the area of the overflow.

smell is gone. btw, poured slowly through the shifter.

beers :beer:

i just took a bit of castoil super degreaser to the area of the overflow.

smell is gone. btw, poured slowly through the shifter.

beers :beer:

Thanks swoope. I plan to get underneath the car and Simple Green as much of the transmission housing as I can when I get back to the States. There's no paint on the housing so it should be okay right?

Thanks swoope. I plan to get underneath the car and Simple Green as much of the transmission housing as I can when I get back to the States. There's no paint on the housing so it should be okay right?

no paint is correct. but simple green will not do it.... gear oil is hard to get off...

beers :beer:

no paint is correct. but simple green will not do it.... gear oil is hard to get off...

beers :beer:

How about the nuclear solution a.k.a. brake cleaner? I have an extremely sensitive nose to both gear oil and CV grease (one from driving an Impreza with a leaky tranny and the other from rebuilding CVs for a summer) and can smell it way before anyone else can so it really bugs me when the car smells. Also, the thing that kind of worries me is that when I was underneath my car the last time I couldn't smell anything and the housing didn't seem to have any dribble. I'll probably also buy a new shift boot since my current one has residue oil in it.

Careful with the brake cleaner. It can possibly ruin seals or other rubber-like parts. It will also cause plastic to become brittle.

I know, that's why I call brake cleaner the nuclear solution.

Rule #1 in public speaking: Know your audience. You and I know what brake cleaner does but the rest of the readers of this thread may not. Then guess who they become upset with when their connectors and seals are wasted because he wasn't clear when he said "nuclear"? :)

Rule #1 in public speaking: Know your audience. You and I know what brake cleaner does but the rest of the readers of this thread may not. Then guess who they become upset with when their connectors and seals are wasted because he wasn't clear when he said "nuclear"? :)

Oh true, point taken.

Yes, thanks for clarifying the possible results of using Brake Cleaner.

Goodbye!
Edgardo

I wonder if engine degreaser might work better?

subscribing as im due for new gear oil this spring ...

thanks for all the good info guys!

IMO you don't have the shifter boot seals installed properly or there is a tear some where. The very bottom boot seal has a lip that needs to fully be seated around the trans tunnel sheet metal opening, the next one seals against that and also is an extremely tight fit around the shifter shaft body. There's no way any undercar smells should be getting past those if they're not torn/bent and seated properly. I would pull it all apart and double check.

IMO you don't have the shifter boot seals installed properly or there is a tear some where. The very bottom boot seal has a lip that needs to fully be seated around the trans tunnel sheet metal opening, the next one seals against that and also is an extremely tight fit around the shifter shaft body. There's no way any undercar smells should be getting past those if they're not torn/bent and seated properly. I would pull it all apart and double check.

I agree, however, even after a thorough inspection, I am still baffled at how the smell navigates itself into the interior... I did clean all the pieces and the smell has died down, but is not completely gone.

FS

Team, the point you make is precisely why most of us with the problem are baffled. Plus, there are several others who ONLY changed the fluid, while not even touching the boots and seals, and the odor presented itself.

my other guess is since i dont have this problem, and i just did it by dumping it down the shifter with the fill plug off to get the right amount in...

if you even get a bit of this stuff on you hand and touch anything in the interior you are going to enjoy it for a while...

beers :beer:

I changed my fluid last August, to RP Maxgear 75w90, using the filler hole. I have never disassembled the console or removed the shifter. Since the change I have had an oil smell, that RARELY enters the cabin unless the windows are open or I sit for a long time at a light with my HVAC on fresh air. When I get out of the car in my garage, however, the smell is pretty strong.

After reading thjis entire thread, I am convinced that this is the problem I have, but I can only smell it from outside the car (thankfully) since I never opened up the shifter.

Some questions:

So, is this something that is unavoidable as a result of the vent design, or can we hope to find a solution?

Is it really appropriate to fill the tranny until it dribbles, or does that end up being more than 1.8qt?

Is there a vent on the rear diff also?

I have the smell on my STU car, but also have the exhaust valve cable running into the cabin from the underside of the lower boot so just assume that's where it's coming in from

another possibility, for me at least

swapped out the differential this weekend, which meant draining all that stinky oil from the trans. When I was putting the new oil back in the trans I noticed there was some oil smearing on the forward bottom of the trans housing. It appears to be some gear oil weeping out the front trans shaft seal and out the weep hole hole in the bottom of the bellhousing just above the rear of the engine subframe. There was zero leakage anywhere else, including the tailshaft seal. It wasn't dripping or anything, just a light smearing that I wouldn't have seen unless closeup under the car with a light

I had already purchased Redline Shockproof oil to install in the trans this time, the Heavy version for max durability at no viscosity increase, when I also noticed this statement in the Redline literature;

"does not produce the foul sulfur smell common to most gear oils"

interesting ....

another possibility, for me at least

swapped out the differential this weekend, which meant draining all that stinky oil from the trans. When I was putting the new oil back in the trans I noticed there was some oil smearing on the forward bottom of the trans housing. It appears to be some gear oil weeping out the front trans shaft seal and out the weep hole hole in the bottom of the bellhousing just above the rear of the engine subframe. There was zero leakage anywhere else, including the tailshaft seal. It wasn't dripping or anything, just a light smearing that I wouldn't have seen unless closeup under the car with a light

I had already purchased Redline Shockproof oil to install in the trans this time, the Heavy version for max durability at no viscosity increase, when I also noticed this statement in the Redline literature;

"does not produce the foul sulfur smell common to most gear oils"

interesting ....


Could you post a picture of the location?

FS

I just finished taking apart my center console and removing the rubber shift boots. There is a sheen of gear oil on my shift turret and both my shift boots had gear oil residue on them. This makes sense as my leather shift boot also has gear oil residue on it. I'm taking it in tomorrow as I don't think there's any way to clean the rubber boots of the gear oil without destroying them, and I don't really want to change the transmission oil in Pepboys' parking lot a third time.

I know correlation does not equal causation, but the last time I changed my gear oil I put in about 1.9 quarts.

I got the smell about a month ago. it comes an go. I thought it was from plastic bag stick on exht or from someone elses car. because the smell only present when I am driving with fresh air setting or just parked. at the same time I notice a leak on my garage floor. at first I thought it a slow drip from change the oil filter. days later oil accumulated,it created a foot wide oil mark on the floor. I decided to put a piece of cardboard underneath to get a gerneral ideal where the oilis coming from. then I drove the car on a ramp and got under it. Imediatly I notice dark oil stains under side of the tranny housing. I cleaned it as well as I could, burned gear oil doesnt come off easily. then I waited to see where the leak comes from. Everything seem to be dry. I notice there s a pair of wire going into something like a lug nut. its on the right side of the tranny. where the wires attached to the nut is oilly. so I gave it a wriggle and notice oil weeping very slowly from the wire grommet that set into this nut. anyone know what this nut is call? it must be some kind of sensor screwed into the tranny. I going to have it replace on saturday.
I read through the whole thread , seem like I am the only one with this problem, oil splatter and burn marks on the tranny housing.

Redline HD Shockproof oil in the trans seems to have solved my smell issue, super smooth shifts despite also adding the AF short throw shifter too :)

Redline HD Shockproof oil in the trans seems to have solved my smell issue, super smooth shifts despite also adding the AF short throw shifter too :)

nice note.

beers :beer:

I can smell oil in my interior for a few seconds after starting up the engine......after that the smell kind of disappear, is it the trans fluid ? or something can some one tell me? I have AT btw

Really good information here. I've had this problem for a while. My question to you guys is this: I had my oil changed with my 30K at the dealership, has ANYone gotten the dealer to cop to smelling the oil? and has anyone gotten the dealer to fix this? i'm pretty pissed that they charged me a crapload to make my car smell like gear oil. Thanks.

Another question on top of this... has anyone else experienced issues with the 2nd and 4th gear synchros after the tranny oil was changed? The dealership already inspected it once (for about two hours while i was stuck there) and found no leaks.

I just went to the dealership this afternoon. They smelled it and am ordering me a new shifter.

Team are you using heavyweight or lightweight or super lightweight?

Heavy for max durability

Mine just recently stopped making this smell.
I wonder if I should be worried?

Mine didn't stop but rather faded away. Its not that bad any more almost unoticable, it just comes up every now and then when im making hard turns.

But then again we might be getting used to the smell...

BTW nice avatar MM

Interesting find on Redline Australia's site:
http://www.redlineoil.com.au/oil-finder-detail.asp?CategoryID=4797&ProductID=7589

Really good information here. I've had this problem for a while. My question to you guys is this: I had my oil changed with my 30K at the dealership, has ANYone gotten the dealer to cop to smelling the oil? and has anyone gotten the dealer to fix this? i'm pretty pissed that they charged me a crapload to make my car smell like gear oil. Thanks.I've had this problem since last June. I've never removed my console or shifter. The mechanic at the dealership can smell the gear oil, but finds no leaks and has no answer to fix it. The smell virtually went away during the colder parts of winter, but as soon as it got warmer it came back.

I'm planning on changing my gear oil in a month or two. Mabe I'll try the stuff that Team was talking about.

^^ What does that have to do with gear oil smell?

Redline HD Shockproof oil in the trans seems to have solved my smell issue, super smooth shifts despite also adding the AF short throw shifter too :)Two questions:

Can I use this in my 8 if it's my daily driver? What do you mean despite adding the AFSTS?

^^ What does that have to do with gear oil smell?Who, me?

I think he was referring to my post. If you click the link it recommends the Shockproof lightweight for our tranny if you race. This is the product Team is using except that he is using the heavy version. I'll tie it all together here: The Shockproof is said not to smell.

I got it.
The shockproof smells the same to me (in the bottle).
I've had more recommendations against the stuff over the years than for it. No science to back that up, though.

With the distinction between cold and warm weather driving and the odor's occurence, I am still tending to think that my theory about flow channels and the technology of clinging fluids are somehow the cause(?).

I changed my tranny fluid out about a month and a half ago with RP75W90 and I know I spilled some so I thought that is why I am still smelling the gear oil. After reading this thread I wonder if I have the same situation. I'll crawl under there and look this weekend. Put mine in the fill hole till it started to come out. I smell it when I get into the car in the garage. Don't notice it while driving.

I have a slight smell in mine for the same reason, but it was much stronger than that after warming up with the old sulphur based oil. That's gone now with the Shockproof oil change.

http://www.redlineoil.com/whitePaper/11.pdf

I'll check again, but at the time I installed it the Shockproof smell was significantly less than the other gear oils I've used in the past

Response from an email sent to Redline:
I just compared the smell of the
MT-90, the ShockProof , motor oil and 75W90. If owners are
experiencing gear oil smell in the interior it may be coming from the
differential rather than the transmission. The MT-90 smells similar
though not quite as strong as the motor oil, the ShockProof is a
little stronger, the gear oil has a very strong sulphur smell. I
would be surprised if you could smell the MT-90 in the car,
differentiate it from general smells.

Regards, Dave
Red Line Oil

Well, I changed my own gear and diff oil to Royal Purple last week and I don't have a single smell of it anywhere.

Bump
Took the 8 in for an oil change, new headlights (film issue), and the gear oil smell.
My dealer couldn't find the source of the odor. They've fixed everything else to date. Anyone else found the source yet?

I replaced mine a week ago. I measured out the 1.8qt and poured exactly that in - new drain and fill gaskets. No smell but much smoother shifting <crosses fingers>. Did not alleviate my high RPM 1-2 shift though. Grrrr.

Doing the diff tonight. I wanted to do them separately to see if maybe it was one not the other - or hopefully none.

I wonder if Royal Purple is just smelly. The dealership changed my shifter, and my leather shift boot, but not the rubber shift boot. My instinct tells me it'll return even though I tried to clean the rubber shift boot as well as I can do it. I lost one of the nuts into the area underneath handbrake assembly in the process too. DOH!

I wonder if Royal Purple is just smelly. The dealership changed my shifter, and my leather shift boot, but not the rubber shift boot. My instinct tells me it'll return even though I tried to clean the rubber shift boot as well as I can do it. I lost one of the nuts into the area underneath handbrake assembly in the process too. DOH!

That nut can be fished out. Try a chopstick (or something similar) and duct tape on the end of the stick. I had to do this for that stupid "fragile clip."

That nut can be fished out. Try a chopstick (or something similar) and duct tape on the end of the stick. I had to do this for that stupid "fragile clip."

It's really really in there. I'm going to pick up a magnet on a wand from Sears after work today.

Currently putting in the Redline diff fluid - man is that stuff stinky and SLOOOOOOW. Much smellier than the trans fluid.

fwiw, it's not how it smells at room temperature, It's how it smellls once it's up to operating temperature. That's when the the real sulphur smells get released

Kinda like your underwear.

Sorry...

fwiw, it's not how it smells at room temperature, It's how it smellls once it's up to operating temperature. That's when the the real sulphur smells get released

Yup. When the car is cold there really isn't any smell. After a 30 minute drive though, it can get much worse.

what exact brand does mazda use stock??

(oh and add me to the list, RP stink.)

I may try shockproof shortly before the real summer heat kicks in here the the northeast.

Just an update, as expected since they didn't replace the rubber boot the new leather shift boot is slowly picking up the gear oil smell as well. I might be getting used to it though since it's no longer as apparent to me, or maybe it's fading, or maybe it hasn't fully permeated yet like before. I suppose putting in a new rubber boot along with a new leather boot will fix the problem, at least for the time being, but I'm going to wait awhile longer and see if the smell gets stronger as at this level I doubt the dealer techs will pick it up and so I would have to pay out of my own pocket for a warranty item that should be free.

While I was swapping the motor, I re-filled with MTL.
After everything was back together, I pressure washed the drive train.

No more smell.

While I was swapping the motor, I re-filled with MTL.
After everything was back together, I pressure washed the drive train.

No more smell.

I'm thinking about going to a MT90/MTL mix next time I change my gear oil.

Redline HD Shockproof oil in the trans seems to have solved my smell issue, super smooth shifts despite also adding the AF short throw shifter too :)
How about an update on this type of fluid please, Team? You mentioned "significantly less" smell. So there is still some odor with the Shockproof? If the smell gets worse when the warm weather rolls in I'll probably swap.

I had the 30k service done by my mech ~6 weeks ago & switched to Redline. It smelled strongly for 2 weeks then went away. But, like CRH, it is definitely on & off since then, with the worst times being after running for a while.

Taking it to the mech tomorrow for a once over - though now that I've found it's fairly common I guess it'll be more of a leak check appointment just to satisfy my curiosity and make sure there's no mess on my stick.

I noticed that the smell gets worse as the tranny warms up. Here in MI the temps have been in the 'teens and 20s for the most part and I get the smell when I get on the freeway for a while but not before. I never really had any gripes with the factory fluid but I guess I'll next try the BG Synchroshift II and if that doesn't show definite benefits, I'll probably go back to the stock stuff.

I flushed my transmission (and differential) oil again and replaced the rubber boots as well as the leather boot. I went back to Redline MT90 for the tranny and 75W90 for the diff. The smell is of course gone from the boot area, but I'm currently getting it through the air vents when the car is warmed up. That smell is subsiding though and I expect it to be fully gone in a couple weeks just like the first time I changed to Redline.

The MT90 itself though, I'm not sure about. I filled about 1.75 quarts of that stuff in; considering capacity is 1.8 and there's probably still some oil in there I don't feel like I've underfilled. However, the shift quality is slightly crunchy at times when the tranny is cold so I have to be careful. This doesn't seem like how it normally is as my past two times flushing my tranny, cold shifting was fine until a few thousand miles later. I'll pay more attention to it, but for the time being I'm going to chalk it down to my synchros starting to wear out.

The MT90 seems to use the synchros in a different way from the Royal Purple though. Royal Purple offered less crunchy shifts, but more synchro whine. The Redline is crunchier, but synchro whine is less. I might try BG next time I flush, unless Team wants to chime in with how he's doing with the Shockproof.

I may have mentioned this in another thread on clutches or transmissions:

I noticed that when the car is cold if I pump the brakes before using the clutch the shifts are much easier till it warms up.

:dunno: at first I thought it might be placebo but I don't think it is. :)

BG Synchro Shift worked wonders for my car. I was having trouble with a grinding shift into 2nd and 4th. It got so bad that virtually anything over 4k was a grind. It's completely gone with the BG in. Very smooth shifting in all gears now. Gear whine is more noticable, but there isn't a hint of grind. I'll take whine over grind any day ;)

BG Synchro Shift worked wonders for my car. I was having trouble with a grinding shift into 2nd and 4th. It got so bad that virtually anything over 4k was a grind. It's completely gone with the BG in. Very smooth shifting in all gears now. Gear whine is more noticable, but there isn't a hint of grind. I'll take whine over grind any day ;)

I hate you. Now I'll be tempted to get it.

I may have mentioned this in another thread on clutches or transmissions:

I noticed that when the car is cold if I pump the brakes before using the clutch the shifts are much easier till it warms up.

:dunno: at first I thought it might be placebo but I don't think it is. :)

The clutch and brakes use the same fluid reservoir...

I changed the trans and diff gear oil last spring with about 10K on the car. Refilled with Royal Purple. I had the gear oil smell the first few times I drove the car afterwards. The smell went away though before I got around to pulling the shift boot.

I'm not complety happy with the smoothness of the shift. Has anyone used any additive with the Royal Purple that they would reccomend?

I changed the trans and diff gear oil last spring with about 10K on the car. Refilled with Royal Purple. I had the gear oil smell the first few times I drove the car afterwards. The smell went away though before I got around to pulling the shift boot.

I'm not complety happy with the smoothness of the shift. Has anyone used any additive with the Royal Purple that they would reccomend?

That's probably just dribble on the transmission and differential casing burning off. My boots were actually contaminated to the point where they smelled like gear oil.

I can't help you with the smoothness issue. The factory fill has probably been the best for me; I want to know what they use from the factory.

anyone else noticed that you only get the gear oil smell when you drive with the windows down ?

^ I can smell it all the time. Sometimes it's so bad I have to open the windows even if it's single digit temps.

anyone else noticed that you only get the gear oil smell when you drive with the windows down ?

Mine was from the boot. Right now it's coming through the vents, but I didn't wipe my transmission and differential casing after changing this weekend so I'm thinking that's what it currently is.

anyone else noticed that you only get the gear oil smell when you drive with the windows down ?

yes,

mine is gone now, but it was only there with the windows down.

beers :beer:

I tried all the known (by me) gear lubes in my trans---ended up with 50% of 75/90W and 50% 75/140W RP Max gear(NOT the syncro shift stuff). The slightly heavier weight ( I have over 50K on my car) is what worked for me.
OSCD

Interesting combo. I'm beginning to suspect this gearbox might like a thicker cold viscosity than what a synthetic 75W90 gives. Factory oil is straight 90 weight.

My next transmission flush and fill is going to be with Amsoil Severe Gear 75w110.

I already received it. They had recommended it as an option.

The rear diff is going to be using the Amsoil Severe Gear 75w90.

The rear diff is going to be using the Amsoil Severe Gear 75w90.As apposed to the front one :p: seriously, why such a light weight in the rear?

Well I have a new to me 2004 that apparantly had the tranny flushed at 30k. It has 32k on it now. Its at Mazda for a display problem and the smell. I doubt they will be able to do anything about it if none of you guys have found a solution.

Should I put a different fluid in the car or try and check the shift boots or clean under the car with degreaser? At least you guys have assured me that it isnt engine oil.

Is the smell subsiding or staying the same?

i know i have seen this issue elsewhere on the forums however i don't recall ever seeing a reason / solution so what about oil / somewhat burning oil smell coming from the drivers side rear wheel? i notice it when i pull in my garage at night. anybody know the cause of that?

taek up the plastic trim that includes the cupholders... wipe away oil. only smells once it accumulates. i threw an air freshner in there and put eveything back. the smell helps.. but the air freshner can asord the oil .. also helpin

The smell is strong. Even in the morning after it has been sitting all night. The wife is complaining becuase of the smell and the fact that it didnt smell when we test drove it. The dealer had it in to repair the heater and they changed the spark plugs, coil and battery because of rough idle. The smell started when I picked it up.

They checked it yesterday and no leaks, smell cause unknown. They are doing the ac amplifier service recall and replacing the radio cage becuase the display scrambles when I tap the radio or hit a bump (unrelated to smell).

If they dont fix it, I will pull up the center console and look for spills.

Does the car smell that way if they overfilled the oil or trans?

Sniff around your leather shift boot. Does it smell like gear oil? A method I find is useful is rubbing your fingers on the leather shift boot where it's recessed as the oil will be first to collect there. If your fingers smell like gear oil after rubbing the boot, your leather boot is contaminated, which means the rubber boots covering the transmission is probably contaminated as well. In that case, both boots will need to be replaced, which should be warranty work, but is a bit of a fight to do it.

By the way, if the dealership changed the transmission oil, they could've possibly overfilled it. The spec calls for 1.8 quarts of oil in the transmission. Generally, the way to tell if the transmission is filled to capacity is to fill until oil starts dribbling out of the fill hole. However, we've found that even when there's fully 2 quarts of oil in the transmission, there is no dribble. Your dealership could've made that mistake and just filled until it started dribbling.

Got the car back today. They said the other dealer had changed theoil and spilled oil all down the bay. They degreased it and it smells like cleaner now, which is better. Ill give it a few days and see if it still smells, and if so I will start looking at other options. They didnt finish my display problem, but instead order a whole radio and display enclosure which will take about 5-6 days to get in. At least I have my car back.

More importantly, it sounds like you're working with a pretty good dealership. ;)

Yea so far I am happy with them. The sign of a good service advisor is that they call you before you call them. Although he did try and sell me a 37k servce that involves fushing all the fluids. I laughed and said, "hey I want to do some of the work to my car haha."

I just had mine serviced 25000 miles. The smell was unberable so I took it back to them. They said it was the cat. Not. It's still in spec. The service writer said that I had a oil seep and they could not track it down. I then came her and looked at this thread and said that's exactly what's happening to my 8. Went to pick it up and told him what I had found. "No, that's not it. It was clean." he said.
No cost. they cleaned it up nice and shiny. I got in and what do you know, I didn't smell anything. When I was driving home from work, there was a faint smell, but not anything like before.

I think there's magic dealer pixie smell remover. Or, they messed something and didn't want to get nailed for it. Just a guess.

I did notice the smell only after I premixed though wich was after the tranny service. Coinsidence or bad timing? Or could be both. I'll not premix the next tank and see what's up.

Cheers

Bill

The smell is still there.

Just as bad. I guess i was wrong about them fixin something.

I'm going to have to look at the trying to use some degreaser.

I have a killer headache from driving around town.

Max

Could it be boot contamination from oil fumes from the top of the turret? I'm noticing it in a lot of RX-8s around here and I think it might be a design flaw...

I still have the gear oil smell nearly two years since the dealership first changed my transmission oil. I've had the car into the dealership and my regular mechanic several times since and they have never been able to pinpoint the cause. No leaks, no spills, no signs of where the smell could be coming from. The one thing I haven't done is pulled the shift boot and reading through these posts it makes sense that it could be the shift boot that's contaminated. So that being said I'm planning on changing the oil again sometime soon. At the same time I plan on buying an aftermarket leather shift boot. Does anyone know where I can get a new rubber boot? I haven't seen anyone selling the rubber boot as a separate item from the "leather" boot.

I still have the gear oil smell nearly two years since the dealership first changed my transmission oil. I've had the car into the dealership and my regular mechanic several times since and they have never been able to pinpoint the cause. No leaks, no spills, no signs of where the smell could be coming from. The one thing I haven't done is pulled the shift boot and reading through these posts it makes sense that it could be the shift boot that's contaminated. So that being said I'm planning on changing the oil again sometime soon. At the same time I plan on buying an aftermarket leather shift boot. Does anyone know where I can get a new rubber boot? I haven't seen anyone selling the rubber boot as a separate item from the "leather" boot.

I got it from my dealership parts department.

I got it from my dealership parts department.

How much did it cost you?

Hi, same issue here for about 9 month now. during winter no sulfur odor windows are up. when pulling down windows. smell is there. Smell is very strong when doing big acceleration or doing a lot of highway. it will never smell if all window are up. Even just opening the "suicide" windows on the highway smell is there. Dealer change the CAT... and has you know it's still smelling. It,s about 2 days now the Service Director of the dealer is runnin my 8 to smell...guest what... they don't smell it...
at least they are not turning back on me.
Guys I read the post all along, do we have a solid solution?

Get under there with a can of brake cleaner and soak the tranny and diff.

I getting back my 8 tomorrow morning. Will have a chat with the Service guy.
thanks for the quick respond that was "rotary" fast.

I got the car back a little over a month ago. They replaced the inner and leather shift boots, cleaned the top of the tranny, flushed the tranny and diff and put new fluids in, did an oil change and reflashed the ecu with the latest upgrade.

Car now idles at 900-1000 so no stutter and I cannot smell the smell as much.
However, my wife, who uses the car two days a week for an hour or so still smells it and says that I smell when I get out of the car after driving home from work.

I wonder if this is from driving it hard?

INteresting stuff. My 04 with 35K just went in for 30K coolant and trans fluid change. Smelled like sulphur. Took it back. They said that the rubber shift boot was cracked and the trans fluid was leaking on the exhaust. He said that they have recently seen a few like this. I also noticed it bad when under heavy accel. Nasty stuff. I'll post tomorrow with the update.

The clutch and brakes use the same fluid reservoir...


OK I am confused (not a wrench so its pretty easy for me to get confused with the technical stuff).

Does this mean that when I top off the brake fluid that I am topping off the gear oil? Is it the same stuff. I assumed that those were separate systems with very different operating temps and needs from a lubricant.

Does this mean that when I top off the brake fluid that I am topping off the gear oil? Is it the same stuff. I assumed that those were separate systems with very different operating temps and needs from a lubricant.

No. The clutch fluid and the brake fluid are the same. The transmission oil is different.

I get the gear oil smell occassionally.
Mine comes from the shift boot sliding up, and not making a good seal around the shifter.
I just lift the center console, without removing the shift knob or anything, just lift it enough to get my hand under there, and I push the boot back down.
I have to push it down about once every 2 months.
But when I smell the gear oil, I know exactly what it is.

So now my dealer is telling me that trans fluid does not smell like sulfer and it may be the cat. Oh boy here we go !!!. Is the cat covered under the 4 year warranty. If so I might just let him put a new one on and then take it back when it still smells.

Sniffed around after driving home yesterday. Funky near the shift boot. I unscrewed the shift knob and man what a stench. Reminded me of the latrine. Let's see how the dealer responds. So far they have been good about this.

i fixed mine from this when i did a better sealing of the emergency brake and the spot where it goes through the trans tunnel.
olddragger

So now my dealer is telling me that trans fluid does not smell like sulfer and it may be the cat. Oh boy here we go !!!. Is the cat covered under the 4 year warranty. If so I might just let him put a new one on and then take it back when it still smells.

Dollars to donuts it's not the cat; it's shift boot contamination.

Ive always used BG syncroshift in my finicky eclipse transaxles and would like to in the 8 but may go to redline non sulfur after this read.

so which redline is right for street use offering better syncro protection w/ the no sulfer smell?

Took it in for 4th time. They "found" some seepage along the seals. No, really? Anyway, they replaced the seal, the shift post, and the rubber and leather boots, again. 200 miles and so far so good. The car smells a little funky, but I think that's just me Seriously I need to detail it as I have not done that since it went sulpher on me. Fingers crossed.

Its baaaack $%^&*

The stink stayed away for a couple hundred miles. It had been a bit cooler here in SoCal so that may have contributed. Anyway, the stink is back. Not as bad as before, but definately there.

I have the car into the dealer for the 4th time now for this problem - they don't have a clue. They have 3 or 4 8's coming in for the same problem and don't know what to do.

Seems to me that the answer is

1) new rubber everywhere - done
2) use non-sulpher based lube - pending
3) clean it up
4) new leather boot
5) clean it again
6) beers and prayer

Anyone found a non-sulpher lube that might not stink when it heats? I can live with an oily smell, but not the rotten eggs stuff.

Thanks

I just changed my tranny oil to RL and now there is a smell plus a strange sound while at idle until I push the clutch, then the sound stops. Is that normal at first? I am afraid to drive it , I don't want to ruin anything.

demon your fine, it happens to us all...trust me dont be afraid

So the sound goes away?

nope, its just the throw out bearing, cant do much about it...just gotta live with it

Update:

47,000 miles. Took her in for motor oil and told them to change the boot and foam insert one last time and that should do it. The smell has calmed down, but there is some residual in the materials.

Tech asked me if it smelled like sulpher (new guy, my previous tech left). I says, ah, yea. He said that "we have a synthetic that we use now that does not smell".

I said "would have come in handy 13,000 miles ago. Anyway they replaced no charge.

Lubromoly 75W-90

http://www.autosportcatalog.com/auto-accessories/liqui-moly-75w-90-synthetic-gear-oil.shtml

Stink seems to be gone, other than the soak in from 13,000 miles of rotten eggs riding around with me. Detailed her (including shampooing the rugs) and so far so good.

That lube look OK to you gents?

Thanks