DIY: Series II Manual Transmission Fluid Change
 

Intro:
This DIY will cover changing your manual transmission fluid in a Series II RX-8. It is pretty much the same as an SI but we do have a different tranny so at least this DIY will provide updated pics. This is my first DIY so bear with me please. I'm gonna write it in the most newb-friendly manner as I am a complete newb myself and its better to to have too much detail than not enough.


When to Do This:
The manual says to do this at 30,000 miles (for severe conditions) or 60,000 miles (normal conditions). I track my car regularly and I like a smooth shifting tranny so I'm going to be doing this probably once a year. It's no more difficult than an oil change so why not eh? Also I've heard its a good idea to do this in the first 5000 miles after a new transmission is broken in. Pics later will show why. Like an engine oil change, you want to do this when the tranny is warm (so the old fluid drains better), but not too hot that it will burn your hands.


Time Required: ~30 - 60 mins



What you Need:
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1. Race Ramps
2. Jack Stands x2
3. Drain Pan
4. Fluid Pump, make sure it fits quart size bottles
5. Jack *I HIGHLY recommend using a floor jack, not a cylinder jack like the one pictured. More on that later...
6. 21 mm socket
7. Torque wrench
8. 2.06 quarts of GL4-type manual transmission fluid. I recommend either Redline MT-90 or Ford Motorcraft Full Synthetic Manual Transmission Fluid. See end for more details.
9. Shop towels for cleaning up any spills


Step 1: Put Car on Race Ramps
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Step 1 Details: I had to back my car on to the ramps because they wouldn't clear the front lip on the R3 bumper. I would recommend putting the front tires on the ramps if you have lower angle ramps. Its good to have a friend to guide you when you are doing this. Otherwise be very careful, you don't want your baby falling off the ramps!


Step 2: Put Other End on Jackstands
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Step 2 Details: It's criticial for the car to be level when lifted or the transmission won't drain properly. Here's where its good to have a quality floor jack. The OEM jack does not go as high as the race ramps I have. So I had to use the cylinder jack from my Jeep. The problem is a cylinder jack is too tall to go under the car. I had to improvise and use the OEM jack to get the car high enough and then lift it the rest of the way with the cylinder jack to get it up on the jackstands.

The location of the cylinder jack in this pic is the factory recommended jacking point and where you should lift with your floor jack. You can lift the whole front end at once from this point. The jack stand locations I chose are a suspension mounting point and seemed to be the most reinforced spot.

*NOTE: Crawling under a lifted car is VERY dangerous. Before you go under, shake the car from several different angles to make sure its secure. Also for added safety you may want to take a wheel off and put it under the car as close as possible to where you will be working.

Here's a pic of the OEM jack location just for fun:



Step 3: Remove Fill Plug
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Step 3 Details: Use the 21mm socket to remove #1. ALWAYS remove the fill plug first. If for whatever reason you aren't able to remove the fill plug you want to learn that before you've drained all the fluid out.


Step 4: Remove Drain Plug and Drain Old Fluid
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Step 4 Details: Now use the 21mm socket to remove the drain plug (#2 in previous pic) and allow the fluid to completely drain.


Step 5: Clean Drain Plug and Crush Washer


Step 5 Details: The drain plug (#1) is magnetic and will collect all the metal chips that are floating around your tranny. This is why some people recommend to do this during the first 5000 miles because a lot of this accumlates as the transmission is broken in. #2 is the crush washer that goes on the drain plug, DONT lose this!

Clean all of that off while you are waiting for the old fluid to drain.


Step 6: Replace Drain Plug
After the old fluid has completely drained, use the torque wrench and 21mm socket to replace the drain plug. The torque spec is below:

Drain Plug Torque:
25-39 Nm / 29-37.5 lbf

Note: It's wise to invest in a quality torque wrench. I used a cheapo from Harbor Freight and the clicking indication was hardly noticable. I badly overtorqued my drain plug and deformed the crush washer. It isn't leaking but I will have to replace the washer next time I do this.


Step 7: Attach Pump to New Fluid
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Step 7 Details: Pretty self explanatory. Make sure you use the extension that will reach to the bottom of the bottle so you can get every last drop of that expensive stuff out of there. Poor Man's Tip: When you switch to the second bottle, dump any remains of the first bottle into the second.


Step 8: Add New Fluid


Step 8 Details: Insert the hose into the fill plug and pump away. Capacity from the manual is 2.06 quarts, but there will likely be some old fluid left and 2 quarts should get you to full. You'll know its full when you put your finger in the fill plug and your finger touches the fluid. Or just do what I did and keep adding until it starts pouring out the fill plug.


Step 9: Replace Fill Plug
http://img135.imageshack.us/img135/7651/pic5h.jpg

Step 9 Details: Now replace the fill plug (#1). Torque spec is below:

Fill Plug Torque:
39-59 Nm / 29-42 lbf


Completion!
Lower your car down off the jack stands and race ramps. Inspect for any leaks, and then take it for a test drive. Try to really get the transmission up to temperature. After the test drive inspect again for any leaks.

Final Comments:
I noticed a big improvement in shifting smoothness, especially when hot. Downshifting from 3rd to 2nd use to be really notchy for me and now its not near as bad.

About the Ford Synthetic:
I used this because it is highly recommended by the Miata guys. The SII RX-8's share the same transmission with the Miata (unlike SI). I can't compare it to Redline MT-90, but the Miata people all seem to think this stuff is better. Perhaps someone who has used Redline will give the Ford stuff a try and post a comparision?

Here's some useful reading from the Miata forums:
http://forum.miata.net/vb/showthread...=270393&page=8
http://forum.miata.net/vb/showthread.php?t=383297
http://forum.miata.net/vb/showthread.php?t=368329

Very nice, thank you!

Thanks for this. I need to change mine soon but I have no ramps so I have to figure something out or just pay to have it done.

You can also use four jackstands. I just feel more comfortable/safe using ramps on one end. Its also a little easier. You can pick up a decent set for around $60. My stealership quoted me around $120 I think for this job. I did it for $50, but that Ford FSMTF is really expensive stuff. You can do it for even less if you use Redline MT-90

Did this today myself at 4900 miles. OEM fluid was in really good shape, but the magnets were covered in funk (grease and who knows what). However, mine took the 24mm sockiet rather than the 21mm. Also did the diff. RL MT 90 and 75w90 GL5 in now.

Do you use the same fluid for the rear diff that you use for the trans?? I need to change the rear diff fluid as well.

Typically no. Trans needs GL4 and diff needs GL5. Some GL5s are safe for soft/yellow metals, but can be too slick and may mess with your synchro mesh. You will get varying opinions on the latter part of that though.

How many miles were on your car when you did this? Was it the first for the car?

Great thread....this is HOW Differential and Transmission Fluid should be changed, none of this refilling through the interior of your car by removing Shifter BS...way more work than needed.

This way, (provided jack floor is level and even) is the perfect and only real way of ensuring you fill the correct amount of oil...that is until fresh Oil starts weeping out of filler hole (overflowing).

nice write up, only thing I noticed was in step 3 you mention using a torque wrench to loosen the bolt. You dont want to use a torque wrench to loosen bolts...only tighten them.

No worries, doesn't work with our series anyway, dont ask me how i know :boink:

So I stopped at the Mazda dealer today to get some transmission fluid to do my first change. This is what he gave me...The description seems a little off but I didn't want to argue as I was on my lunch break and didn't have time. Mazda part # 0000-77-5W90-QT Does this look right? Or should I look elsewhere?
Attachment 235711
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Attachment 235712

Redline versus Motorcraft MTF
 

There are a lot of guys using the Ford Motorcraft Trans Fluid over at the US Miata/MX-5 forum.

Basically it is the same transmission internally (well MX-5 NC2 is)...they share 95% of the same parts as the Series II RX-8 Trans.

And yes I have heard the same responses from those who have changed from MT-90 there.

Me, well I use MT-90 in both my P66M transmissions and are happy with the results.
Frankly IMO we are only talking small + and -.

Anytime when fluids are renewed there is a perceived and real difference, put on some miles or kilometers and the differences are minuscule.

IMO MT-90 is better when Trans is at full operating temperature, where the MC is better when box is cold, Motorcraft is also slightly thicker when compared to MT-90.

Both are good products, as are most of the mainstream Gear Oils when the correct one is used (that is to Mazda's spec's).

I see many owners ignoring what Mazda says, either using GL4 or GL5's in the wrong applications.

What would be the negative you say?

FWIW, I have been using the FM fluid for the past thousand or so miles, gotta say it feels a LOT better than the Redline to me. I used to have this terrible grinding/notchy shift from 1-2, which seems to be remedied or lessened by the newer fluid, and yea the fluid is pretty thick compared to the redline, took a hell of a lot longer to pump it into the tranny. (thats what she said)

Redline felt great on the track, as Ash indicates it needs to warm up. I will see how the MC does on the track before giving a final opinion, but right now the MC is feeling about the same to the Redline with the exception to the 1st-2nd shift. This is still better than Redline, but isnt quite as good as a couple days ago.

Precisely what I have said...

Thicker is better for a cold trans feel, but when a trans is hot it prefers thinner, and runs cooler when hot.
Remember we don't have oil coolers on MT's.

ALL gear oil 'additives' or so called 'improver's' are an oil thickener which is claimed to help notchy or noise issues with transmissions - diffs.

Fucking retards at the local mazda dealer decided that my trans complaints could be solved by draining half my tranny and refilling it with ATF.

8800 miles, already had the trans rebuilt due to syncro failure on 4 5 and 6. It's been notchy and crap since I got it back, with frequent grinds between 2 and 3.

Should I be worried about the ATF in there and demand it be drained? Make them take it apart to find the real problem?

This was a common fix for older vehicles. I remember it being very popular in the Nissan scene when my buddy picked up a 300zx way back when. It basically remedied hard shifting on a cold transmission while protecting when the tranny got hot.

Not sure how it would affect our transmission though.

Good to know. Annoying that they did this when my complaint had nothing to do with stiff shifting. The problems I'm having occur hot or cold...

Contact Mazda USA, and ask them if that is a Mazda recommended fix for your transmission. If it isn't, you want Mazda USA to tell the dealer to drain the ATF out of your transmission, and fix the issue correctly.

BC.

Surprisingly, this half assed blend seems to have diminished the problem. No more grind at higher rpms going from 2-3, although I can still feel a slight burr there. I will most likely be doing a flush/fill in the next 2 weeks based on the directions here using the Ford Synthetic.

I still don't know why this SII transmission has felt like weak, notchy garbage compared to the unit in my 2004 RX8 :suspect:

As Paimon said using ATF is not new..in fact FWD Mazda's use it in MT's.

ATF allows trans to get hotter faster and being much thinner makes changing easier.

There has been no change in S2 Synchro's, ONLY 5-6.

Contrary to what you think the S2 (P66M) trans is a better made one than the Y16M series used in the NB Miata and 2004 Series 1 RX-8.

Not suggesting you have, but many owners are using or have used the wrong grade/type of MT Oil and damaged S rings.

If the wrong thing is in there, its all on the dealer. It's been very stiff and unpleasant from new, figured it would wear in a bit. As it started to smooth out, the syncros failed and the dealer did a rebuild. That was at around 7500 miles.

I was more worried that the atf trick was just to shut me up for a few months in the hope that my warranty would be up. As long as its working, I guess I can't complain. Thanks for the input and advice guys! :)