2005 GMC 2500HD Allison Trans Fluid

[Bsin12]

What is the most current recommended trans fluid? Is it is Allison TES-295?
.
I am thinking of switching to Eaton PS-386 as I have it readily available at work and we use it on most of our on-highway automatics. TES-295 specs at cSt @ 100 - 7.4 PS-386 is a little thicker and comes in cSt @ 100 - 14.8. Is that too thick and will it cause problems or decrease fuel efficiency? I’m probably just asking for trouble but it never hurts to ask. Thanks.

 

[Tomioka]

Eaton PS-386 is most likely a gear oil with that viscosity and used in Automated Manual Transmissions (AMT), not in torque converter automatic transmissions.

 

[Jetsfan421]

I'd stick with a tes-295 fluid. Probably costs more, but it's the right stuff.

 

[zrxkawboy]

Eaton PS-386 is most likely a gear oil with that viscosity and used in Automated Manual Transmissions (AMT), not in torque converter automatic transmissions.

That’s my guess, too.

 

[weebl]

I would only use TES-295.

 

[nascarnation]

Any Dexron III will work fine.
You've got a transmission designed for 26000 lb commercial trucks and school buses.
TES-295 is certainly the best you can put in it, but if funds are scarce, then a TES-389 (Dexron III).
The Eaton lube is for countershaft transmissions.

 

[BlakeB]

Summit has gallons of Delvac TES-295 for 33.99 or 4 Gallons for $127.99, with free shipping on orders over $99. At ~$8 per quart shipped to your door, why experiment with anything else?

Mobil 1 122062 Mobil Delvac 1 ATF | Summit Racing

Free Shipping - Mobil Delvac 1 ATF with qualifying orders of $99. Shop Transmission Fluid at Summit Racing.

www.summitracing.com