MT654 transmission oil. Change to straight 10W

[Mario]

I dropped the MT654 valve body on my 1991 M936A2.
Before I put new oil in, considering putting straight 10W vs OEM 10W40.

If my reading is any good, it appears that the HD transmission fluid is straight 10W oil, which is basically a cold version of 10W-40
I'm looking for 1st hand opinions of people that have done it and. what your results are.

Also, in googling, I did find this video from 6 years ago of an older A0 or A1 unit.
I think all the transmissions were the same, but I could wrong.

I asked question on the YT, but don't know if the creator is still active.

 

[simp5782]

Switch to ATF, specifically transynd if you want to decrease transmission temperature and increase longevity. It's cheapest from summit in Mobil.

Transmission internals are the same thruout except A2s use a different front pump and torque converter ratio.

 

[Steelreaper80]

My oil supplier has this in stock and it is a really good price. Would this fluid work?

 

[simp5782]

My oil supplier has this in stock and it is a really good price. Would this fluid work?

It's dextron 3

 

[Steelreaper80]

It's dextron 3

I will just go with this. Especially for the first change. I know I won't get all of the fluid out so there will be some mixing between the old and new. Second change I will go with the Transynd.

 

[Tow4]

I used Traveller Premium Universal Tractor Trans/Hydraulic Fluid from Tractor Supply. It has the Allison C-4 rating.

 

[Steelreaper80]

I used Traveller Premium Universal Tractor Trans/Hydraulic Fluid from Tractor Supply. It has the Allison C-4 rating.

They also have the Tractor/Hydraulic fluid in stock and it is C-4 rated. How is your transmission after the change?

 

[Tow4]

No problems.