Gentlemen I need your assistance

[Fastfunco]

Stupid question but im leaving on a 400 mile trip in my M925 A2 tomorrow morning--
Upon general maintenance - I found both rear diff are low on oil. about 1 inch below the fill plug-- and there are no leaks present.
I have only 927 miles on this one and the military did a 98k frame off rebuild on it in 2010- I think the frame was the only original part used in rebuild-- front and read diffs were replaced at time of rebuild-- as they are listed as replaced on the work order -

Oil in both rear diffs is brown-- needs to be replaced--

What is the best replacement oil to use ??

I have looked at the TSBs for over an hour and just can not get an answer I am happy with - and it is getting late- can you guys please help me out?

 

[davo727]

I think its just plain old 90 wt gear oil

 

[davo727]

About 3 gallons per axle.

 

[ClintA]

I use 80W-90 in all of mine, hope this helps

 

[5tonman1971]

I use 80-90 in the rears and I used 85-140 in the front axle. But I do believe the TMs recommend 80-90

 

[Fastfunco]

Thank you guys--

I use 80-90 in the rears and I used 85-140 in the front axle. But I do believe the TMs recommend 80-90

Thank you guys-- it sure is nice to have you guys a Post away-- I really appreciate your help!!

 

[Fastfunco]

one more thing- any reasoning behind the rears being an inch low and the front is topped off???

 

[MtnSnow]

Regular GL5 80/90weight gear oil is what is called for. you can pick it up in 5 gallon pales at just about any auto parts store.

 

[5tonman1971]

one more thing- any reasoning behind the rears being an inch low and the front is topped off???

It might have evaporated over the years or was leaking at some point and never refilled. Or was never filled correctly to begin with if both rear diffs are the same level.