I have been doubting the claims made by people who changed their tranny fluid to Redline. I doubt no more. I went with a MTL and MT-90 50/50 mix and I wish I had done it earlier. It now shifts much quicker with none of the sticky feeling between gears. I should be able to shave at least a few tenths of a second off of each shift. Let the auto-x season begin!

For those with auto-x withdrawls that play GT3 to ease the pain, check this out:
https://www.rx8club.com/australia-new-zealand-forum-37/got-bored-so-i-built-47445/

 

Damn. Am I the only one not feeling any difference after a Redline upgrade? I have had it for a month now and I don't feel any difference at all. It's still notchy in the 2nd gear shift and even in the 4th sometimes. I can also hear my tranny whine more than before. Could it be that the dealership installed it wrong? That they switched the fluids with the Differential? Would that make this effect? I clearly marked my bottles with Transmission and Differential markers. Maybe the installer was being a smart *** thinking I marked my bottles wrong and installed it his way. Is there any way I could verify this or not?

I'm thinking about just forgetting the $60 I paid for the install and buy new bottles of Redline fluid and installing it myself. I'll have Christmas vacation to do it anyway.

 

Double check and make sure your rear differential fluid is not the 'ns' version which is for non-slip differentials.. Your correct fluids should be MT-90 for the transmission, and 75w90 for the differential. Most stores have the 75w90 and 75w90ns sitting right next to each other.. it's very easy to grab the wrong bottle. Putting non-slip fluid in a limited slip differential is bad ju-ju

 

Running a 50/50 mix of MTL and MT-90 myself. Did this mostly to confirm that the constant tranny noise is, in fact, the pilot bearing (which it is).
Not really any noticible difference in shift quality, but my transmission was smooth as butter to begin with.

I'll probably replace the release and pilot bearings in the spring anyway. I'd really like to get rid of the "whirring".

 

Yes, I ordered the right fluids online fro Hare Racing's website. The bottles said 75w90 and MT-90. I'm really guessing that the installer at the dealership switched it thinking I was wrong in marking the bottles. You know how it is, some people get smartass when it's unnecessary.

 

The main difference for me was that I used to hold presure on the stick from first to second and movement would pause until the syncros did their thing, and then it would slip into gear. Shifts probably took me a second or more. Now it is one motion with no pause and using less preasure on the stick. :D

I also hear a bit more whine when I let out the clutch while in neutral.

 

Replace them with what? Can you hear the "whirring" when you're driving or at idle with the windows up?

 

Good question, unless there has been an upgraded part released by Mazda the option is to try and find something from a specialist bearing supplier. No point putting another OEM one back in......

I can hear mine whirring away at idle with the windows up.

Gomez.

 

Its the "normal" whirring in neutral with the clutch out that we have all noted.

I'll put in fresh replacements directly from NTK (Mazda's supplier for bearings) instead of the Mazda part.
I think they were all installed with too much runout and grind.

Can't hurt.