6MT Transmission Fluid Recommendations
 

I have the usual 2nd gear issue when cold. The original fluid was pretty bad, so I changed to Motul Gear 300. Now in colder temps 2nd gear is almost impossible to engage before the fluid heats up. After reading that the OEM fluid is closer to 10cSt @ 100c, I realize that maybe the Motul Gear 300 is too thick.

Any recommendations for a thinner 100% Synthetic GL-4 gear oil I should use? Here are some that I found:

Pentosin MTF 2 (GL-4)
100% Synthetic
Vis@100°C 7.7 cSt
Vis@40°C 38.3 cSt
http://www.pentosin.net/specsheets/Pentosin_MTF-2.pdf

RedLine D4 ATF (GL-4)
100% Synthetic
Vis@100°C 7.5 cSt
Vis@40°C 34 cSt
http://www.redlineoil.com/product.aspx?pid=51&pcid=9

Fuchs Titan Sintofluid FE SAE 75W (GL-4)
Synthetic?
Viscosity?
http://www.fuchslubricants.com/titan...uid-fe-sae-75w

Thanks for any recommendations and advice.

Almost everyone suggests Motul, but you could get some Amsoil in there, quite a few people like that and use it not only for DD but for track duty.

I saw a lot of negativity toward Readline..plus the readline fluid you specify is for ATFs but I a sure for a DD you will be fine.

Motul sucks in the cold. Absolutely terrible, as I'm presently finding out. I'm gonna have to see about pentosin.

@Ferrari, I'd be interested to see where you read:


After reading that the OEM fluid is closer to 10cSt @ 100c, I realize that maybe the Motul Gear 300 is too thick.


Does it list the cSt @ 40c?

hm..id be interested as well in what the members suggest..
I was about to change my M/T fluid to motul 300 along with my first oil change.
but given that i live in Canada and Winter being around the corner..
makes me rethink my decision on M300..

I live in the northeast.. and My trans does feel a bit clunky compared to most other cars I've driven..

I was curious to know if Motul 300 is still recommended even for colder climates like up here in the Northeast.. As long as there is not a significant amount of snow on the ground I'll pretty much daily my car.

Motul Gear 300. LOVE IT!

Probably irrelevant because I'm in a warmer climate.

Im thinking I'll probably go with the Amsoil.. seems to be the next best choice outside of motul with colder temps.

I'd recommend Redline MTL, which I believe is 75w85 GL-4. While on stock fluid, I couldn't shift into 2nd gear in the morning and MTL helped a lot.

Please don't put D4 ATF in your manual transmission.

Let me try to put into perspective just how bad the Motul gear 300 is. In the 5-10 deg C mornings that we've had for the last week or so, I've had to double clutch for the first ten minutes of my commute. Otherwise it would skip over the teeth of the synchro before it would engage. It really felt horrible. That fluid had about 2000 kms on it.

Today I switched out the Mutol for a 50/50 mix of redline MTL and MTL-90. The MTL-90's specs were very similar to Motul's and the MTL looked like it might be too light considering the cars its recommended for. So I ended up with the mix. I'll report my findings in a few days.

Pentosin FTW here in the Pacific Northwest. Been very happy with this stuff

That is a good blend. I've tried that myself, and it is the only thing that felt as good (almost) in the cold as Pentosin.

Yeah my local race shop is more familiar with redline so I went with it. But I wouldn't mind trying pentosin.

It was 8 deg c this morning. Shifts in the cold were a little off, but WAY better than motul. Its still not as smooth as I'd like it but I'm fine with this at $150 to have the fluid changed.

I should probably add that shifts are as good as stock now.