i have an 04 rx8, with 71k miles on it. and it seems to grind gears when i down shift from 6th to fifth, its also making some squealing noise like a cricket or something..... seems to be coming from the rear maybe.. underneath


Grinding is most probably due to clutch or synchromesh that is worn out...


Cricket sound i assume would be wither ur coilovers or ur rear bush mounting...

i have 15k on my car and i am starting to feel the same symptoms.

My second gear grinds at high RPM. downshifting into first from anything more than 9 mph also grinds. when im at idle in neutral, the tranny is noisy, and it squeels, like a hamster wheel that needs oiling. when the clutch is depressed, just a slight whirr from my rotors....


Forum search found this.. sorry for the old post quote.

My transmission just started squeaking like a bad belt- and only does it when the clutch is in not depressed in neutral (tho I could swear I heard it once when driving in 1st gear slowly near a wall). It does not do it all the time, but does it daily now. I just noticed it last week or so (thought it was a belt issue at first).
My 04 6 speed RX8 has just 42k miles- and Mazda Knoxville replaced my engine (under warranty) just 600 miles ago.

What exactly causes this? I noticed if a barely tough the clutch pedal, the squeaking changes pitch. Is this a clutch issue, or a transmission bearing issue?


EDIT- found this thread shift fork grease detail to be very informative.

http://www.rx8club.com/showthread.php?t=172605

Hey everyone,



I picked up a 2004 rx8 last week and proceeded to change the transmission fluid (recommended at 60k), then shortly after it started grinding into 2nd at high rpms. I used OEM fluid, so I can only assume the previous owner knew about the problem and changed the fluid as a fix. I've done some research and it appears that most gear grinds are from the clutch, shift fork/synchros, or the clutch pedal about to go. Correct me if I'm wrong, but if it was a delaminated clutch wouldn't the grind be in more than one gear? The clutch pedal feels fine as far as I know, so that leaves the expensive part(s). From what I've read a 1st-2nd grind is common on these due to a faulty shift fork design; which Mazda supposedly revised. Does anybody have any experience/ further information on a fix for this. I've seen people chase gear grinds with fluid (which im not completely opposed to), but consensus seems to be that it only masks the problem. Any input would be greatly appreciated. Thanks in advance.

I just had my trans pressure plate and throwout bearing and clutch replaced at 159K..It's as smooth as silk. Local shop only charged me 1045.00. Next I'm getting a remaned motor.:)

Ok, so I suppose it's time to add in my two cents. My 04 RX8 has just over 86k miles on it and my fourth gear is being difficult. Based on trial and error, I can downshift into fourth from fifth at anything under 5k RPM. Anything above that causes a grind and clunking sound. More recently though my second gear is to starting to act funny too. Downshifting into 2nd for things like sharp turns occasionally causes it to miss the gear. Sometimes it'll downshift into 2nd just fine, and other times I'll hear and feel it screaming at me as though I didn't depress the clutch enough to complete the shift.

As for the stats on it, my car is still original for pretty much everything. The clutch system is the original, the tranny is original, and the engine is also still original. I have no aftermarket parts set on it at all, yet. I'm just looking for some help on what could be causing this. I've read up on the synchros and how that may be the problem, however I'm not a mechanic. If it is something as serious as needing to rebuild the tranny then I guess I'll just go bend over the dealership.

I drive a '04 rx8 6sp with about 140k miles on it. I recently replaced my entire clutch with an Exedy stage 1 clutch kit after mazda advised me my clutch plate and throwout bearing were going bad. After going through nearly 750 miles of break in period, i get a hard grinding into 2nd gear still. I'm not noticing it really in any other gear, just 2nd at any rpm over 6.5. Also i cant downshift into 2nd unless im around 30mph. I skimmed over this thread, but there is so much it was hard for me to get any answers regarding this problem.

Need new transmission or rebuild it to a much better spec. I'm surprised that after a million posts on this thread, people just don't outright say the transmission, though smooth when working, is absolutely garbage in terms of taking abuse.

My transmission when I had an 07 GT was replaced at 27k miles when it started hard grinding when going into 2nd at the top of 1st, and also, as mentioned, would not go down into 2nd until very low speeds for that gear (30mph).

My transmission when I had an 07 GT was replaced at 27k miles when it started hard grinding when going into 2nd at the top of 1st, and also, as mentioned, would not go down into 2nd until very low speeds for that gear (30mph).

Did that solve your problem? Because right now I'm at 40k on my 07 GT and I'm having the same problem.

Yes, replacing your transmission will solve any transmission problem...
Though, a smarter investment would be to go to a transmission specialist shop and rebuild the transmission to much higher specs.

Yes, replacing your transmission will solve any transmission problem...
Though, a smarter investment would be to go to a transmission specialist shop and rebuild the transmission to much higher specs.
Yes u r right because i do the same thing... :-)

Thanks guys. I'm trying to do whatever I can to avoid a tranny swap but damn. It's looking more and more like that's what I'm going to have to do. I don't seem to have the problem shifting into 2nd when the car is on a full tank of gas though...anyone know why that may be??

no...that's just all in your head, no offense. fuel has nothing to do with mechanical part failure in a sealed transmission case.

Thanks Zeal. Since I also seem to have the issue of not being able shif into 2nd gear at all at high rpm's im thinking i might just end up replacing the throwout bearing, and clutch since it kinda feels like its just not engaging completely(i did learn standard on that clutch so i probably screwed it up.lol) and hope that solves the issue. If not a tranny rebuild it is! >:|

I got my car back in 2005 with 9k on it is a 04 and am also a mechanic, in my case the dot 3 in my master cyl ran low and since the clutch slave share the fluid with the brake system it created a air pocket on the line wish lead to a bad slave. So technicly I will step on the clutch but it wouldn't fully disengaged the clucth on the transmission I rebuilt the hydraulic components but the damage is alrdy done after I fix the hydraulic system it shifts better but once the fluid get hot and thynn second gear start acting up so my solution is synchromax for now .

I bought my RX8 new it's an 08 6 speed. since it was new I experienced some minor grinding on 2nd gear, took it to 2 different Mazda dealers here in the Tampa Bay Area and they both said. Sorry we cannot reproduce the problem. so I gave up, now of course I'm out of warranty and Mazda will pay for the parts, and I have to pay for labor. I am not happy at all. The car has 46k miles , but is over 5 yrs. The powertrain is 5 yrs or 60k.I see after reading a lot that I am not alone. What can I do? Mazda has a case number of my problem, any suggestions will be greatly appreciated.:tear:

get the fluid change and see how it goes.... if not... either have the 2nd gear replaced or just the synchromesh if ure tight... If not, then both please...

Well, looks like my RX-8 has hit the chopping block now. The clutch went to the floor yesterday and when I investigated it further I found that the clutch bracket has warped to the point of not even touching the brown switch located on the back of the clutch pedal. Oddly enough it still hasn't snapped though.

get it to the dealer for a free replacement

Issue:

Hard to shift, it's a constant resistance for all gears, not so much it not wanting to go in gear but it's requires more stength

- Replaced tranny and diff fluid with MT like a year ago. This issue was most noticeable 6 months ago
- Going to test my clutch tonight; I don't believe its out, doesn't exhibit signs of slipping

I have a 3rd party warranty so i might have mazda check it out. I'm just sensing thoughts... I ran a query but no one had any firm fixes.
http://www.rx8club.com/search.php?searchid=8561531

I dont drive my car, but going on to highway I do give it a little gas b/c if I give it to much I hear a metalic click from transmission, 05 rx8 70k... just to throw that in there :)

same issue here :( 06 gt with 56000km and driving hard in first, i cant put it in second, nor downshift from 3rd to 2nd. . I have 3rd party warranty however the cover syncros, only if broken not worn , and to determine that, i need to take it apart and hope its broken lol

ok I have done a little searching and cant find it...I have a leak that appears to be coming from right before the shifter underneath, the 2 peices that are bolted together ....I am not sure if that is where the rear main seal is or what...I cannot find anything about it, but a friend that also has a 8 has said thats a common place for it to leak...any suggestions? btw I have a 2004 with almost 130K miles and a manual trans

here is what im talking about...is that sealed with just gasket sealer or does it have an actual gasket seal?:dunno:

if im seeing it right, there is a thin orange 'gasket' or sealer of some sort. U need to have an expert opened it up and place a new seal and he will also apply a grey sealent to seal it properly

Do I have to get it done by a pro? I have taken transmissions out before...is it a seal or just some sealant? And what is the name of that seal then? I don't want to get ripped off by the dealership.

Just stopping in with an update. I had my fluid changed to MT-90, along with replacing the clutch (bad), master cylinder (bad), and slave cylinder (bad) and now the car grabs gears and drives better than ever! No grinds or hesitation between gears at any speed that I've tested.

I've had similar problems with mine. Real hard 1-2 shifts and grinding 4th gear, as i have mentioned in a couple of my other posts. Still no solid explanation...
http://www.rx8club.com/showthread.php?t=222180
http://www.rx8club.com/showthread.php?t=226753

Got my trans oil changed a few weeks ago before my motor blew and shifting has improved in smoothness but feel universly heavier in all gears.

2nd gear has always been iffy and the fluid change has improved feel and action when the trans is warm but now seems much worse when cold.

Should I try a different trans oil, Redline?

Hi People
I have been having problem when downshifting from 3rd to 2nd at higher speed (so i will be at 6000 RPM in second after downshifted).
It grinds...so after reading it up a bit, people seem to say that it's the synchro having problem.

Can you someone explain how it works and why it is causing the problem?
And
what I can do to fix it?

Thanks

Hi People
I have been having problem when downshifting from 3rd to 2nd at higher speed (so i will be at 6000 RPM in second after downshifted).
It grinds...so after reading it up a bit, people seem to say that it's the synchro having problem.

Can you someone explain how it works and why it is causing the problem?
And
what I can do to fix it?

Thanks

It's either a bad sychronizer or a bad shift fork. I've deducted that my 4th gear's shift fork has somehow become damaged and doesn't function fully. Your's might be the same, although if you are rev matching perfectly on the down shift then that might be the synchro. If it is either, it'll most likely be cheaper to just get a new transmission considering labor costs of dismantling a transmission, repairing it, and reassembling it. OR, it might simply be a matter of you not correctly rev matching. Try double clutching into second, i.e. be going in 3rd, pop it into neutral, take out the clutch, rev to like 7-8K, then clutch in and shift into 2nd. Worked for me when I was learning to drive a manual. 2 main options: live with it, or fork over the dough for a new (or used) tranny.

Got my trans oil changed a few weeks ago before my motor blew and shifting has improved in smoothness but feel universly heavier in all gears.

2nd gear has always been iffy and the fluid change has improved feel and action when the trans is warm but now seems much worse when cold.

Should I try a different trans oil, Redline?

Mine has the same issue. It seems as though its that "Friction Modifier" BS that they put in your oil. If you let the car warm up first to like the second dash, then drive, it makes it MUCH smoother. Honestly, I'd switch to Redline without any friction modifier in it.

I know this is an old thread, but all the more reason to post this. I started getting a 2nd gear grind in my 04 rx8. I replaced my tranny fluid with amsoil 75w-90 first, still had the problem, then I used that royal purple 75w-90 and the grind actually got worse, so I switched out to the REDLINE MT-90 and no grind at all and every gear now feels like new. Both the Amsoil and the Royal Purple where GL5 and the REDLINE MT90 is GL4,, so maybe that was the problem all along. Either way, my 2nd gear no longer grinds and I am a happy camper.

There you go! REDLINE fixes all your tranny problems!
Transmission case cracked? Add some REDLINE!

Tranny cracked? Come on. All i am saying for a normal driver the redline really helped. and took the grind away, for how long we will see, but it definitely helped my particular situation.

Tranny cracked? Come on. All i am saying for a normal driver the redline really helped. and took the grind away, for how long we will see, but it definitely helped my particular situation.

I was exaggerating

right ive looked through 32 pages and i didnt see my problem... ive just sold my SZ-R JZA80 supra with the getrag gearbox so i know what noises to expect with a heavy duty gearbox. but the one in my '8 type s has what could be a buggered bearing (possibly on the lay shaft) well it sounds incredibly rumbly when the clutch is engaged and it disappears when the clutch is disengaged... also when in 1st through 4th and 6th gears the noise is present but not in 5th (which im going to assume is 1:1 ratio? like my supra was) this has lead me to believe that the problem exists on my lay shaft if its anywhere. my getrag made a similar noise (not quite as bad but it was still there) so i was wondering is this a normal noise?

Is it like a wrirrrrrrrrrrrrr with a tiny bit of shuddering? Mine does the exact same thing. And 5th is 1:1. But I'm not sure if its really a problem. There might be a bad layshaft bearing but i think that since the lay shaft is mounted to the transmission case itself (through use of tapered thrust bearings most likely), then I think its just the rotational energy being transferred from the lay shaft to the case and in turn the rest of the car. And you wouldn't really notice it when you're moving since all the other road noises and sounds.

Go here:
http://www.rx8club.com/showthread.php?t=43673

+1 More beleiver for Redline MT-90. Swapped fluids today and it seems to have smoothed everything out and it doesn't grind in 2nd or 4th quite so much. its the first day but everything seems to be better. Say 90% better.

I found MT-90 a bit stiff, a little heavy - I mixed in about 1/4 to 1/3 of Redline MTL which is a lot thinner.

Have used that mix for the last eight years, lovin it!

Hi guys, I picked up an 06 M/T sport a week ago, got the plate on it Wednesday and started driving it. Last night on my way home she started acting extremely strange, too high in the rpm range for the road speed.. things like that, me being able to hit the accelerator in 6th, watch the RPM jump like crazy and see no reflection of that in my road speed. Then, I stopped at a stop sign, and she wouldnt get above 20 mph in any gear, so I pulled over, and when I tried to pull back onto the road, I had exactly 0 clutch engagement of any kind.... ANY ideas?!?!

I know there is a really long thread, and it's a pain when I'm sure the answer must be here somewhere... but I'm freaking out... please help?

:bowdown:

I am no expert, but if the engine revs and the car don't move appropriately in the manner you describe, sounds like a fried clutch... A new one installed should be $750 or less.... If it grabs when its cold and then doesn't grab when its hot, the clutch is completely worn out. Just my 2 cents worth.

Either a bad clutch or a bad clutch slave cylinder, either way will cost a little dough, but that's sort of implied with an RX-8 :P

I know this is an old thread, but all the more reason to post this. I started getting a 2nd gear grind in my 04 rx8. I replaced my tranny fluid with amsoil 75w-90 first, still had the problem, then I used that royal purple 75w-90 and the grind actually got worse, so I switched out to the REDLINE MT-90 and no grind at all and every gear now feels like new. Both the Amsoil and the Royal Purple where GL5 and the REDLINE MT90 is GL4,, so maybe that was the problem all along. Either way, my 2nd gear no longer grinds and I am a happy camper.
I also have a '04, and I changed my tran fluid to redline mt-90 about 5k miles ago. It was like you said silky smooth, but now I can feel it wanting to grind especially 2nd to 3rd and 4th to 5th. I've read several praises for motorcraft fluids with our trans, so I might go that direction here soon.