6MT Transmission Fluid Recommendations

[FR-S89]

hey guys what's the OEM fluid for this transmission? Does anyone know where we can buy it?

I have no problems with shifting or anything.. but i like to swap every 50k and coming from a Honda... i won't use anything but OEM

[N234]

Originally Posted by FR-S89

hey guys what's the OEM fluid for this transmission? Does anyone know where we can buy it?

I have no problems with shifting or anything.. but i like to swap every 50k and coming from a Honda... i won't use anything but OEM

I'd phone a dealership. Get price and brands as they could be different.
I've noticed they sell different brands of engine oil from place to place.

[twag4]

Originally Posted by mhughett

Since Redline MT90 is a 75w-90 gear oil, does it would feel any differently than OEM?

MT 90 is manual transmission oil. MTL is manual transmission limited slip differential oil. For front wheel drive cars with limited slip diff in the transmission. Some of the hot hatches need this.

[Ferrari]

Originally Posted by twag4

MT 90 is manual transmission oil. MTL is manual transmission limited slip differential oil. For front wheel drive cars with limited slip diff in the transmission. Some of the hot hatches need this.

Not quite, they are the same in terms of additives, it's just that MTL is thinner than MT-90. They can both be used in the BRZ's manual transmission, although I'd recommend MTL since it's the same viscosity as OEM fluid.

http://www.redlineoil.com/product.aspx?pid=45&pcid=7
http://www.redlineoil.com/product.aspx?pid=46&pcid=7

[twag4]

Originally Posted by Ferrari

Not quite, they are the same in terms of additives, it's just that MTL is thinner than MT-90. They can both be used in the BRZ's manual transmission, although I'd recommend MTL since it's the same viscosity as OEM fluid.

http://www.redlineoil.com/product.aspx?pid=45&pcid=7
http://www.redlineoil.com/product.aspx?pid=46&pcid=7

Our cars come with 75w90 in the USA. According to my owner's manual anyway. And MTL is for front wheel drive trans with limited slip diff inside- according to redline.

[Ferrari]

Originally Posted by twag4

Our cars come with 75w90 in the USA. According to my owner's manual anyway. And MTL is for front wheel drive trans with limited slip diff inside- according to redline.

I checked Redline's website again. NOWHERE does it say that MTL is for LSD transmissions only. MTL can absolutely be used in the BRZ transmission.

OEM fluid is a 30 weight at 100*C (check the UOAs on this site). MTL is a 5W-30 oil, so roughly the same as OEM fluid at operating temps. MTL will probably be better in colder temps too.

[twag4]

Originally Posted by Ferrari

I checked Redline's website again. NOWHERE does it say that MTL is for LSD transmissions only. MTL can absolutely be used in the BRZ transmission.

OEM fluid is a 30 weight at 100*C (check the UOAs on this site). MTL is a 5W-30 oil, so roughly the same as OEM fluid at operating temps. MTL will probably be better in colder temps too.

I didn't say limited slip only btw. Besides it needs limited slip additives added I would think. You're right it can be used. But,when I called Redline this is the info they shared with me. MT90 is a 75w90 GL4 oil. My owners manual calls for 75w90 GL3. GL4 supercedes GL3. MTL is 75w80. This is not the same. If I wanted something that analyzed the same as stock fill, I'd go with stock fluid. The problem is that people have shift issues with stock fluid. For me, MTL makes no sense, because it doesn't solve any problems that I had- minor gear grind from 3rd to 4th. MT 90 fixed it, worked great in the cold, works great in the warm. Redline told me this is the fluid for our cars. It was great advice for me. YMMV

[twag4]

Originally Posted by Ferrari

I checked Redline's website again. NOWHERE does it say that MTL is for LSD transmissions only. MTL can absolutely be used in the BRZ transmission.

OEM fluid is a 30 weight at 100*C (check the UOAs on this site). MTL is a 5W-30 oil, so roughly the same as OEM fluid at operating temps. MTL will probably be better in colder temps too.

Rereading my previous posts I can see why it looks like for limited slip transaxle only. Sorry about that, it was not my intent. The redline web site did say something along these lines back when I was looking into the issue. It was vague, this is what prompted me to call redline and ask. The tech I talked to gave me the info that I shared with you.

[AZP Installs]

Originally Posted by Ferrari

I checked Redline's website again. NOWHERE does it say that MTL is for LSD transmissions only. MTL can absolutely be used in the BRZ transmission.

OEM fluid is a 30 weight at 100*C (check the UOAs on this site). MTL is a 5W-30 oil, so roughly the same as OEM fluid at operating temps. MTL will probably be better in colder temps too.

To be honest IIRC the manual for the BRZ specs 75w90 GL3 (which has been superseded by GL4) and according to the RL site the MTL is 75w80. You will probably want the MT-90 if you are going the Redline route.

http://www.redlineoil.com/content/fi...%2010-13-1.pdf

Personally we use the Motul Gear 300 75w90 as it's both MTL4 and MTL5 and can be used in both the Trans and Rear Diffy.

-mike

[JS + BRZ]

Changed out my stock fluid in transmission and differential to Motul 300 yesterday. I had so much gunk in the stock oil. The car feels much smoother now. It feels healthier for some reason.

[504]

Currently I have redline MTL in transmission and Redline 75w90 GL5 in diff


It seems there's a common trend to put crazy on paper specced fluids to make themselves feel better. "100% synthetic" this and "gl5 certification additives" that. Clearly I have fallen for this as well considering my choice of fluid but I do hope that I help at least one person in saying that better specification on paper does not necessarily translate to better shift performance. I don't regret changing out diff fluid at all but transmissions are much more sensitive to fluids and this is felt every time you drive. Each transmission is different and performs best with a fluid it was tailored to run on like OEM. Now of course there will be the odd miracle fluid like perhaps the pentosin mtf2 which seems to have the ideal coefficient of friction for optimal synchro performance but it achieves better performance while being a thinner fluid and may not be ideal for people in hotter climates as seen by Dezoris' UOA (stock fluid at 10cst @ 100C is thin as is)(btw this is coming from a guy that is a big advocate of thin fluids).


My redline MTL has all the signs of greatness; an amazing base stock with an amazing additive package but the problem is that it is too amazing. It is too slippery for ideal synchro engagement leading to a crunchy second. And now I sit here looking for somewhere to buy stock fluid to perform another oil change.


I am not in any way suggesting all name brand oils wont be suitable or that redline mtl will be crunchy for your purposes in your climate but I am merely suggesting that significant research needs to be done for tranny fluid to make sure you don't regret it. Personally, stock fluid was amazing. It sometimes blocked me out second on my first shift during cold weather but other then that it was perfect. I still don't regret replacing my tranny fluid as I was really happy to flush out wear metals but I just wished that I was content with the stock oils performance and that I replaced it with oem. So just putting it out there, if your stock fluid performs good (or even good enough), be careful changing brand as it may start an endless cycle of fluid experimenting!


EDIT: Added 1 quart redline 75w90 and 2nd gear issues 95% resolved.
EDIT2: thicker mix did nothing to reduce 2nd gear crunch. Redline for tranny appears to be too slippery for my case atleast

[ZZT86]

Originally Posted by 504

. . . stock fluid at 10cst @ 100C is thin as is)

No doubt it sheared down to that from a much higher spec @ 100C. The full synthetic MTF2 has a KV of 7.7 @ 100C, a fluid I have tried which has a similar KV as MTL & I concur it too didn't feel right even when hot, definitely better when cold although I must confess the clutch pushrod adjustment wasn't where it should have been. I have dumped & retained the MTF2 for future trials and currently using my preferred oil - Motul Gear 300 = 75W90 !

[Fizz]

Originally Posted by ZZT86

No doubt it sheared down to that from a much higher spec @ 100C. The full synthetic MTF2 has a KV of 7.7 @ 100C, a fluid I have tried which has a similar KV as MTL & I concur it too didn't feel right even when hot, definitely better when cold although I must confess the clutch pushrod adjustment wasn't where it should have been. I have dumped & retained the MTF2 for future trials and currently using my preferred oil - Motul Gear 300 = 75W90 !

Are you finding the 300 better than MTL and Pentosin MTF2?

[ZZT86]

In my limited driving of late I found that the MTF2 improved shifts 1-2 & 2-3 during winter although it felt more mechanical when it got to normal/hot temps - I was feeling more of the gearboxes harshness as a result of the lighter & therefore less insulative effect a lower viscosity oil has. I haven't bothered trying the MTL but do have the Gear 300 in there atm and I do find it to be the best compromise - normal/hot temps it's great whereas during cold startup/temps it isn't much different than the stock oil as you would expect as they're both the same weight. The Motul is a full ester synthetic so I would expect it to last a lot longer than the Toyota fill.

I will try the MTF2 again soon as it's getting cold here again, ehhh, as I recently flushed & bled the clutch master/cyl & reckon I got the clutch pushrod adjustment as good as it will ever be.