Allison transmission fluid

Bones454 · May 12, 2020

They say using Allison trans fluid makes a difference in shifting and running cooler what’s your thinking on this is it a good idea.

unit · May 13, 2020

The new Allison 10 speed trans, 10L1000, used in the new 2500HD's calls for a different fluid than is used in the older six speed trans, Allison 1000. So I think I'd stick with what is recommended by GM for each. I doubt you could tell the difference at any rate. I used Transynd fluid made specifically for Allison transmissions in my 08 Silverado with the Allison 1000 when changing fluid and filter but I couldn't tell any difference in the way the trans shifted or felt. Transynd is considered to be a superior fluid and I used if for longevity of the transmission but any quality fluid might have been just as good. It would take a scientifically accurate test with many fluids and transmissions to know for sure and I don't think anyone has ever done that. Many transmission builders recommend changing fluid often over using the most expensive fluids. They simply suggest using any quality fluid and change more often. I tend to buy into that philosophy.

newdude · May 14, 2020

On 5/12/2020 at 10:08 AM, Bones454 said:

They say using Allison trans fluid makes a difference in shifting and running cooler what’s your thinking on this is it a good idea.

Bad idea. DO NOT use Allison Transynd in your 2020.

The "Allison" 10L1000 uses DEXRON ULV Automatic Transmission Fluid ONLY. No other Dexron ATFs are compatible (III, IV, HP) with this fluid, nor is Transynd (which is a Dex III fluid).

The 2020 Allisons have a thermostat on the transmission cooler lines to allow the trans to reach optimal operating temperatures faster for fuel economy.

Edited May 14, 2020 by newdude