I'm getting ready to change the differential fluid in an 2003 3500 4X4, how do i know if the axles are limited slip or not? do I use a modifier in the front diff.?

 

The limited slip differentials on the 3rd gen trucks don't require any friction modifier at all.

 

Guess that is why the Chilton book only lists "Mopar Synthetic Gear lube SAE 75/90" on the 2500/3500. It does however list a modifier for the 1500 truck. Thank you for your input!

 

You're welcome! And I stand corrected; the 1500 trucks still use the old Chrysler 9 1/4 axle with a traditional clutch style limited slip unit. The 2500/3500 trucks went to AAM axles in 2003 and use a different style of limited slip unit.