I will be changing my differentials fluid on my 4x4 it seems like theyre leaking, any tips on how to change them, what kind of fluid is recommended and a good gasket and a where i can find some chrome differential covers?

 

Use a large catch pan, it can get messy..... any gear oil should work.. i prefer Valvoline just remember to add the friction modifier if you have a limited slip differential....


Chrome parts are a dime a dozen on ebay!

 

how do you know if you need friction modifier by the type of differential you have I think my truck has a 3.92 or something im not realy sure I forget how I found out what I was last time.

 

You only need friction modifier if you have limited slip.

 

I am needing my diff fluids changed soon. I cannot remember if the front axle on the AWD systems have limited slip? Can someone confirm?

 

ya just found out im a 9.25 cause im a 12 bolt do they come with the LSD or is the only way ill know is by opening it up

 

Nope, there were no front LSDs.

There should be a stripe or a tag that says if it has it. Easiest way to be sure is jack up the back end with it in park and the parking brake off, then spin one wheel. If you can't spin it it's LSD, if you can spin it and the other spins the other way, it's open.

 

There is a tag on the axel or the sticker in the glove box.

You also need a rear diff rubber cap. That's the common source of leaks.

Fluid is personal choice. If I remember correctly mine is 185w90. **** they use in freightliners and Mac trucks. Truck will be dead by the time that fluid need changed..

 

If you read the labels on the gear lube some of them have the friction modifier already in the lube, Mobil I believe has it as well as others but these are more expensive.

 

I've heard of problems with that stuff that has it pre-mixed into the oil, same with engine break in oil. Do it right and get the regular oil and add the friction modifier to it yourself.