ok, this is my first post. i hane a 2005 ram 2500 4x4 with the obvious aam 14bolts front and rear. i just changed the gear oil for the first time today, and i want to make sure i used the right stuff. i put in 75w90 mobile 1 synthetic at a great 8.99 a quart!!! thats insane. the book said that the aam axles dont require an additive for limited-slip, just that u use 75w90 synthetic. am i ok? if so, any other suggestions on what else to use next time? all feedback is greatly appreciated

 

If you want to use Synthetic then I think you would be better off using Amsoil 75W-90 Severe Gear Oil. I use this in every pickup truck that I have owned. Yes it cost more than regular oil but it is better on the gears. Where I use to work/drive we used Amsoil Synthetic in the rear ends of the Semis and it holds up very well.

Charles

 

I really don't think you'd ever see a difference in using Mobil 1 vs other top synthetics such as Royal Purple, Amsoil, Red Line, etc. I think you did just fine by choosing Mobil 1 75w90 as your fill of choice. As far as the LSD is concerned, you did the right thing and didn't use friction modifier, because they do not require it.

Here is some interesting reading on the use of thinner weight oil and conventional vs. synthetic.
Interesting reading considering many of the brands are going to 5w20 as factory fill these days (Talking about crankcase not diff here)


Oh yeah, [sm=welcomesign.gif] to DF

 

cool thanks guys, i appreciate it. now ill rest easy