Transmission Fluid Recommendations?

[Tom]

Since I'll be in the area changing my fuel pump, I thought I'd change the transmission fluid too. It's an LSD S-spec transmission. What's the latest and greatest on transmission fluids these days? Fairly sure I used Mobil 1 last time. Also looking at Redline and Swepco... Have any of them emerged as a clear winner in recent years?

[cda951]

Swepco 202, it's a synthetic version of 201, so good for LSD transaxles but offers improved shift quality (I've always used 201 in my own 951 with LSD, shifting a tad notchy when cold, but great wear protection for track use). 202 is pricey but worth it, has even been a worthy band-aid for worn second-gear synchros on a couple of customer 951s.

[gpr8er]

Greg Brown did my LSD way back maybe 12 years ago. The Quaife diff had a bolt that backed out and trashed the case sawing a hole in the bottom. I will never buy another Quaife, customer service is horrid. Absolutely no fault of GB. It was a sweet tranny while it lasted. Anyway GB said Mobil 1 75/90

[Gaspowered]

Very timely topic, as I'm wanting to change the fluid in mine as well.

Anyone have experience with Amsoil 75/90 Severe Gear Oil?

Cheers

[blueline]

Very timely topic, as I'm wanting to change the fluid in mine as well.

Anyone have experience with Amsoil 75/90 Severe Gear Oil?

Cheers

I love Amsoil's Severe Gear (all their products actually). While I've never used it in my Porsches, I have and continue to use Severe Gear and Signature Series syn oil exclusively in other vehicles such as my GMC. Their filters are top-notch too. I used their products exclusively back in the day for race and track cars too. Great product and great company.

[Thom]

Motul gear competition 75W140.

[Tom]

It's nice to see such a strong consensus.

[blueline]

vintage-gargoyle-mobiloil-cc-gear-oil_1_f429c9fda803d963f0a71d3db76bd111-3673391201.jpg (191.5 KiB) Viewed 418 times

Ignore the recommendation for use in Fords. It works fine for other makes too. Coats and Cushions the gears for quiet operation.

[Belgian951]

I'm on the lookout for Red Line MT90 75W90 GL-4 0.94l RD-50309 but I don't have a LSD transmission.

[icb]

I use Red Line MT 90 as well, but I too have an open diff. I believe it will work with an lsd, maybe you'll need an additive. Definitely check, I'm not 100%. Anyhow, I love how the shift feel is, even when cold it still shifts great. It doesn't smell bad, and it's even a nice color! It transformed my transaxle. One thing though, if you have been running a thicker oil like swepco 201 and there's wear in your trans or differential gears/bearings, the mt90 won't mask the gear noise like the swepco did.