[PSDStu]

Never done this before but it looks like all I need to do is to remove the diff cover, drain the fluid, and refill through the side plug.... is that all there is?

 

[Deib]

It is that simple.

If it is a limited slip differential you need the slip additive unless the oil you are putting in it says you don't need it.

I used mobil 1, it said I didn't need the additive, but I had a clunking noise until I added it.

 

[PSDStu]

Thanks.

It is a Limited Slip rear end..... does the Ford 75W 140 have the slip additive?

 

[Soaggydogg]

Correct, pull the diff cover and I clean it out with rags/towels. Then refill through the drivers side plug and check the vent line for blockage while you are doing this. Do not over fill. I have used Redline, Amsoil and Schaeffer’s diff fluid. From my experience do NOT add the friction modifier until you add the fluid of your choice and then go to parking lot and do slow speed figure 8's. If the rear end grabs add some modifier and retest.

I am happy with the #267 from Schaeffer’s with no modifier for front and rear diffs.

 

[spaceballs]

I like Schaeffers also. I found that when I added the friction modifier it would start leaking out of the diff.

So I run it without it on my LS. Man that stuff is so slick you can hear it gliding in there.