I've had my 2009 rx8 for a few months now and just recently 5th gear started to grind only when I'm at highway speeds and only when I'm coming from fourth. I did some searching and it seems like it could be anything from changing to the transmission fluid to replacing the entire tranny. I also saw on this one guys website http://www.mattharrell.net/personal/rx-8.html that when they changed the transmission to the one similar to the Miata's they didn't have carbon coated syncros on 5th or 6th gear. Is this actually true and if so when I take this to a dealer would it be possible to get this thing completely covered and paid for by them since it seems to be a big fault with the 2009+ transmissions? How would you handle the dealer?

 

Try a quality gear oil. How many miles on your trans? Def could be a synchro/5th gear. But obviously fluid change is cheaper than a trans

 

Isn't the car still under warranty?

http://www.mazdausa.com/MusaWeb/disp...ehicleCode=RX8

Take it in...

 

only 21000 miles on the tranny, yeah i looked over all the paperwork and it should all still be covered

 

This may be a really silly question and I tried looking it up but could only really get transmission advice on other cars but I was just driving and noticed that my third gear throw feels a lot different then it used to, not quite as smooth and clutch feel going into second gear has changed too. Is this normal for cars, for the throw of the shifter to change as you drive the car or am I screwing this tranny up and its slowly breaking. Like I said it could be a very stupid question, also i checked the clutch fluid levels and its at full.

 

It could be your gear going out.

I'll just quote myself to save me from re-explaining my recent issues:


For most of the ~13K miles between me buying the car and finally getting a rebuilt transmission, my transmission felt great, up until 5th started grinding.

I'd get yours checked out.

 

'ober' IT would really help IF you could fill out your User CP, top left corner banner of the forum and fill in your 'signature', like put the year and some brief details about your RX-8, auto/manual.

It REALLY helps those of us that you want a reply from, so please do it, so I don't have to search to find out what RX-8 YOU are talking about and what type of transmission...OK

M8 you have been here long enough..

 

Have you changed trans fluid lately?
The synchros are sensitive to the lubricant and friction modifiers. Try some Redline MT90

 

'Ober' ...... I suggest you go to a Mazda Dealer with your other Tranny issues and read up on the 2009 Tranny threads right here in this sub-forum....if you believe you still have a B2B warranty.

PM me your VIN number the (JM1FE.........) and I can work out more information for you about your Tranny and what needs fixing..OK

Ash

PS and DO YOUR SIG...

 

+1 Agree with DarkBrew

 

I haven't changed the clutch fluid, just added a little about 4000 miles ago because it was below the full line. My car has about 25000 miles on it and actually about 4000 miles ago my 5th gear started grinding as well. Only for the first shift into 5th and only at highway speeds around 55-60 mph. If i tried changing into fifth around 45 just to see if it would grind and it never did. I took it into the a dealership they said they couldn't recreate the grind but took the tranny apart anyways and said everything looked okay. They took it apart and resembled it in about a day too which i thought was really fast. Oddly enough i drove out to colorado from nj about a month and a half ago so i'd have car at school and the 5th gear grinding stopped for awhile, i guess maybe because of all the highway driving. But now after just a bunch of short city trips around Boulder CO i got on the highway the other day and there was a grind going in 5th gear. It just feels like my tranny is constantly changing. Looking over the DIY i don't think i have the materials to change the tranny fluid nor the money to get them right now. I might take it into the dealership but i'm only 20, do you think they'd give me a rental? I'm not sure what else i can do.

 

Until you've put 20,000 miles on the car, the transmission isn't really broken-in yet. So really you've only recently gotten to a point where the gearbox's performance will be stable for a long period of time. On the other hand, after 20,000 miles of breaking-in, the trans fluid is probably shot to hell and it's time to change it. I swapped my trans fluid for Redline MT90 like others here and it works great.

But yes, your transmission IS constantly changing. If you've mostly driven automatics, or FWD stickshifts, you've been "protected" from noticing all the day-to-day changes that occur inside a complex mechanical system like a transmission. Even a few degrees' difference in temperature can make it feel different. Because the RX-8's gearshift goes straight into the transmission, with no intermediate linkages or rubber bushings to smooth-out the sensations transmitted from the shift forks to your hand, you'll notice every little change in the gearbox's behavior as it ages. That's just the nature of this car.

Regarding the high-gear synchronizers: I occasionally have some grinding when I go into 5th or 6th gears, and I've discovered I can solve it quite handily by trying to shift into each gear with the clutch closed at a stoplight. The synchronizers SHOULD resist shifting under those circumstances; if they don't, then I repeatedly try to shift into the problematic gear, lightly at first, then more firmly, until I can press hard against the shift lever for a second or two without any grinding. This procedure burnishes the synchronizer friction surfaces to remove any gunk that's built-up on them.

 

yeah the rx8 is my first ever manual car so i'm a little paranoid and a little new to the whole experience. Do you think I could buy the fluid and have some place install it for me? You guys seem to love the redline fluid so i wanna go with that stuff but like i said i can't install it myself. Thanks for the advice too fyrstormer, but by clutch closed i assume you mean not pressed in at all right?

 

Yes, that's what I mean.

Any independent shop can install whatever trans oil you bring with you.

 

REDLINE MT-90, or ENEOS

I have had experience with factory and royal purple 75-90 the GL-4/GL-5 and the like.
Redline and eneos are the best I've tries so far I have redline in now used to grind 1 to 2 hard driving now its smooth as silk.

 

alright so Redline MT-90 GL-4 and i guess i need to buy about 3 qt?

 

yepp that's it and you only need 2 quarts for the tranns, and a transmission fluid pump it will take about 15 mins to DIY its very simple.

check the links below:
2004 RX-8 Transmission & Differential Refill

 

Might as well change the differential oil too. So yes, 3 quarts. I think I bought 6 just to be super-sure I'd have enough even if the shop spilled or lost some. Not like I won't use it eventually anyway.

 

'ober' thanks for your VIN Number..

Sadly (like me) you are one of the 3,405 Series 2 RX-8's that have these questionable 5-6 Synchro Rings and 6th Gear.

So just so you and others know..
Mazda upgraded the two 5th and 6th Synchronizer Rings, 6th Gear, Reverse Gear, and 1st and 2nd Shift Rod Shafts...That was/is all.

IF your Gearbox repair was done correctly from the start you should not be having grinding issues now.

My 2011 MX-5 has virtually all of the S2 Internals (updated ones) and 5 and 6 change is great, BUT...I don't change at the same RPM that I do in my RX-8.

IMO this is part of the issue, the original S2 trannies takes many miles to wear in and more than one Oil change...but they do not like High RPM changed up or down under load from 5 to 6 or 6 to 5, I would not recommend changing above 6000 RPM...PARTICULARLY when car/tranny is not hot, or a cold box.

My S2 Tranny is the original (untouched) with the older parts and I don't have an issue, I don't 5-6 shift above 6000 RPM....I know others will flame me down...so be it.
ALL other gear changes YES to redline many times, but not 5 and 6.

There has been some good advice already given, I really doubt you will see your trans giving you breakdown problems.

 

What is the range of VIN numbers with the problematic transmission parts?

 

FWIW, my 2010 sport had terrible results with Redline. Very notchy shifts and lots of 1st to 2nd grinding. Replaced with Ford Motorcraft fluid (big with the Mx5 guys) and the tranny is smooth as butter.

 

When i took my car in for the tranny the guy said everything looked great but like i said he seemed to be very quick in his assessment so he might not have really looked. Finally managed to locate some redline MT90 and it turns out i have a friend who has ramps. Now if i could just find jacks for the front and a torque wrench i should be able to do this myself. It seems like 24,000 was a long time to change the fluid so i hope the tranny is ok. Thanks for all the help everybody its much appreciated

 

Whenever you change lubricant composition, there is always a period where the new lubricant doesn't work right, because the old lubricant is embedded into the outermost molecular layer of the parts being lubricated, and it takes time for it to be scrubbed off. Burnishing the synchronizers by trying to shift while the engine is running and the clutch is closed speeds up this process.

 

The transmission won't have any problems caused by old oil with only 24,000 miles on it. There might be something else wrong, but if so, the oil had nothing to do with it.

 

IF the last 6 digits of your S2 VIN Number is under # 403405 (which is actually your cars serial #) in North American (Australia the VIN Serial # is below #300689, for UK below #300922) you own 'a' Transmission with questionable 5th and 6th gear Synchro Rings/Cones, plus "other parts" revisions/updates above those VIN Serial #.

Or an easier identification option is, all cars in all regions made before Oct 18, 2010.(Vehicle Production Date) will have some internal Transmission parts updates which 'could' become a reliability issue with age or use.*

Listed below are all the parts revisions (and FINAL) to the S2 P66M Manual 6 Speed Transmission in the 2009-2012 RX-8.

IF your car was made after these Production Dates, or has a VIN Serial Number higher than
those shown here for each of these individual parts revised/updated then you have the latest and greatest Transmission parts already installed.

Shifter (stick, gear stick, gear lever) all made before July 08, 2008. Below VIN Serial # 401850 NA, # 300254 AUST, # 300516 UK, The NEW Part now is # P610-17-510D

6th Gear all made before Sept 15, 2008.........................................Below VIN Serial # 402410 NA, # 300565 AUST, # 300714 UK, The NEW Part now is # P603-17-630

1st and 2nd Shift Rod all made before Nov 01, 2008.......................Below VIN Serial # 402821 NA, # 300630 AUST, # 300831 UK, The NEW Part now is # P601-17-411A

Synchro Rings (two) all made before April 21, 2009.......................Below VIN Serial # 403405 NA, # 300689 AUST, # 300922 UK, The NEW Part now is # P612-17-26YA

Reverse Gear all made before May 17, 2010...................................Below VIN Serial # 403406 NA, # 301103 AUST, # 301266 UK, The NEW Part now is # P601-17-281A

1st and 2nd Clutch Hub all made before Oct 18, 2010.....................Below VIN Serial # 405251 NA, # 301172 AUST, # not sold UK, The NEW Part now is # P602-17-261

Or if your S2 RX-8 was produced after Oct 18, 2010 then you also have the most up to date Mazda made Transmission and parts available today.
I also see NO further changes to the S2 6 Speed Transmission from Mazda.

* I must stress, this information listed does NOT necessarily mean that you will have a reliability or performance issue with your Transmission.
Nor does it mean that Mazda is obliged to rectify said issues before or after your RX-8 warranty expires.
There is NO recall or TSB (a TSB for UK and Australian markets exist) for the 5-6th Synchro Gear grinding for the North American market.

"How does Mazda work", well you must present your car to an authorized Mazda Dealer while under warranty and complain of the problem(s) you are having...like "grinding of gears when changing into 5th or 6th Gear", or 'pops out of 4th Gear', never say I read here on a forum that these parts were updated and I want them in my car when your car is not showing any symptoms related to these revised parts...you will get nowhere at your dealer.

ONLY use this as a reference when you definitely have an issue and when you are getting stonewalled by your dealer or Mazda.

Part Numbers in blue are interchangeable ONE WAY ONLY... New part for old, but NOT old part for a New Install/Repair.
The other revised parts are less critical and can be used in either direction....New part for old and Old part for New Install/Repair.

Mazda JAPAN really wants to know what YOU are experiencing as you see it, what are you feeling and hearing when a warranty claim is made by a dealer.