6MT Transmission Fluid Recommendations

[roddy]

Originally Posted by Chanpion

@Ferrari Have you been out in -20ish weather yet? Curious. I'm guessing there are not as many twin owners as you go to colder places.
It's was averaging -25 a few weeks ago for me and I wouldn't mind having a working 1st and 2nd gear.

I also use the Pentosin fluid that @Ferrari currently has in his. We don't quite get the prolonged cold you do out there, but on the mornings when it has dipped to -20 or lower, it still works good. I only get a slight catch into 2nd on the very first shift of the day (even then it's not very common). No fluid is going to be perfect at those temperatures with no warm up time.


If you can't find Pentosin, or it is too expensive, The Redline mix that @Calum is using also works good. If you go that route, try 1L of MT-90, and fill the rest (~1.3L) with MTL. I used the opposite (1L MTL + 1.3L MT-90) and found it not quite as good as Pentosin below -10C or so.

[billyk]

At the risk of cross-posting, and being repetitive, if the OP is concerned about getting from 1st to 2nd in cold weather, there's a really simple potential solution, and it doesn't involve changing gear oil.

When cold, just consider pulling away slowly for the first 5 seconds or so, and staying in 1st for that duration before shifting to 2nd. Repeat if needed during warm-up.

That 2nd gear syncro will have the chance to spin-up, and 2nd will be totally smooth, with stock gear oil, in the single digits. Simple.

Caveats:
- This works for me, every single time, but I can't guarantee it'll work for you. I get that.
- If you want "better" gear oil, that's cool. I am not suggesting you shouldn't chase your passion to tweak your FRS.
- This technique does not address downshifting to 2nd when cold. That's still an issue for the first couple of minutes.
- Please dont' suggest that double-clutching fixes this. For me, it doesn't.

I just want to suggest that for others (especially newbies, like I was) that changing gear oil might not be the only way to go if 2nd gear is a bitch in the cold. For me, it was not like 2nd gear was "tough" in the cold, it was "impossible". Simply letting that syncr spin-up has resolved my issue 100%.

Good luck!

[NLSP]

I switched to Motul Gear 300 last week. Temperatures have been ranging from 2 to 12 degrees. I don't have the issue of getting into 2nd like most people talk about. I've just noticed it's a little harder getting going from 2nd to 1st when it's cold. I pretty much have to be at a complete stop. Before I could slip it into first around/just under 10km/h.

Otherwise, I'm loving it, noticeably smoother than before. Put it in the diff as well.

[hmong337]

I've got motul 300v in my gearbox and it does fine in -25°c. Not sure what people are expecting out of a frozen gearbox here. It will be clunky with no matter what fluid you stick in there during cold weather.

[sam69]

I recently changed the original oil and put Nulon in ....... http://www.nulon.com.au/products/Gea...Transaxle_Oil/ and even though it's warmed up here have noticed better shifting even in the cool of early morning.

Overall pretty impressed so will see how it goes come winter.

I used their GL-5 in the diff with Penrite LSD additive and all harness has completely gone .

[Ferrari]

@Chanpion, I don't use the car in winter anymore, I'm back to my old Golf TDI. I drove the BRZ when it was -15C or so and it was quite bad.

The Golf has Motul Gear 300 in the 5-speed gearbox and it's always smooth, whether it's -30 or +30. The BRZ was horrible with Motul Gear 300, and better with the Pentosin, but nowhere near as smooth as the Golf at lower temperatures.

BTW, my issue has always been downshifting from 3rd to 2nd when cold, not upshifting from 1st to 2nd, which is ok. Revmatching doesn't help either.

[RJasonKlein]

I run Millers Oils lubricants and highly recommend them, and I'm particularly impressed with their gear oil. Here are the recommend products for our cars:

Differential Oil
- Millers Oils CRX LS 75W90

Transmission Oil
- Millers Oils CRX 75W90 NT

Engine Oil
- Millers Oils CFS 0W20 NT

They're expensive, but they rock!

[grodenglaive]

Originally Posted by frslee

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.

I've had the redline in since May. Compared to the oem fluid in the summer, well... it shifts a bit easier overall, but the 1-2 clunk is even worse.
In the winter though - it's much better than oem. No issues shifting at -25 C.

I was thinking about trying the motul 300 until reading this thread.

[AZP Installs]

I think a lot of the negative anecdotal information about the Motul is from a small sample size. We go through about 300-500 gallons of Motul Gear 300 a year in our customer cars so our sample size is pretty large. We also use it in our personal vehicles as well and in our track BRZ. The amount of times we've had customer complaints can be counted on one hand.

We are located in NY/NJ which sees both cold and hot as well as lots of bumper to bumper driving.

We find it to be very smooth and it also is GL4 and GL5 compatible so you don't have to use a different fluid between the trans and the rear diffy. Amsoil also makes a great product as well as Millers. All of which we've used and have had great success with.

-Mike Paisan


Maintaining, Modifying and Educating TriState Enthusiasts since 2001.
Like us on Facebook! | E-mail: sales@azpinstalls.com | 725 Fairfield Ave | Kenilworth, NJ 07033 | 908.248.AZP1 (2971) |AIM: AZP Installs
"Race Tested, Enthusiast Approved!"

[Ridgerunr]

Has anyone tried Royal Purple products, I used it in my NSX gearbox a while ago and seems to work well. Never drove the car in cold weather, so I don't know how it would be in the winter.

[mhughett]

I have quite a bit of Royal Purple Synchromax and Max-Gear and was thinking about a formula containing about 2/3 Synchromax and 1/3 Max-Gear. The 75W-90 Max-Gear is for both gearboxes and differentials and is both GL4 and GL5 rated while Synchromax is about the same viscosity as Pentosin MT2. I used Synchromax on all of my prior BMW's and it worked great, including at the track.

[weedtank]

Anybody know what the service interval for the tranny and diff is?

[n8dog11914]

Originally Posted by RJasonKlein

I run Millers Oils lubricants and highly recommend them, and I'm particularly impressed with their gear oil. Here are the recommend products for our cars:

Differential Oil
- Millers Oils CRX LS 75W90

Transmission Oil
- Millers Oils CRX 75W90 NT

Engine Oil
- Millers Oils CFS 0W20 NT

They're expensive, but they rock!

I just ordered their new 'Premium' 75W-90 brand transmission fluid. I'll let everyone know how it goes. I would have got the race stuff but I only do about 4-5 autocrosses and 1 track day a year.

http://performanceracingoils.com/ee-...-oil-p-87.html

[continuecrushing]

just installed Motul Gear 300 75w90 non-ls in trans/diff this past weekend.

My trans felt pretty good before, but its like butter after the swap. Very pleased!