Hey guys, im about to change the fliud in both diffs to amsoil severe gear and with a mag-hytec cover in the rear. Do i need to add a friction modifier and if so, do i double the ammount to compensate for the extra fluid capacity? Thanks
Does the rear diff use a friction modifier?
- Thread starter CHYKYNLIPS
- Start date
No, you do not need friction modifier for either diff. You need to run a full synthetic oil in the rear, if it's equiped with the g80. Seeing how your going with Amsoil, just fill it up and run it.
It is!
Run the amsoil and forget it. 100,000 miles under normal conditions and regular towing like campers are a car every now and then, more often if you work the truck like an excavator! No modifier NEEDED!
Enjoy the piece of mind.
doh! my bad, I was thinking of the older pre-GMT-800 14 bolts. 
:
Ive used regular 75-90 gear oil in them though with no problems.
:Ive used regular 75-90 gear oil in them though with no problems.
Adding friction modifier in those diffs will quite the disks from "chirpping" and keep them from "grabbing". Most aftermarket LSD's will require a modifier.
You don't need it in most cases. ONce in a great while someone might get some chatter. The amsoil severe gear has the additive already in it so no worries.