Hey guys i have a 99 4wheel drive and 2week ago i was offroading and my friend was watching and said both rear wheels were spinning and when it was in 4 wheel drive all 4 wheels would spin but my door tag says "axle 19" which if i'm right its a non posi but the tag on the diff is missing so i'm not sure what kind of diffs i have. Any suggestion? Thanks

 

It's possible the diff was switched out. I had mine switched from non limited-slip to limited-slip since it's a 2X4 and wanted all the traction I could get. I think the diff covers are different from non LS to LS so you may be able to tell just by looking at the shape of the cover. Try this website:

http://www.ringpinion.com/b2c/DiffLi...=Diff&TypeID=4

 

Yeah it probably was cuz the owner before me was a volunteer fireman and i could tell the truck had been offroad when i bought it but i'll look at my diff cover tomorrow and see. Thanks!

 

Diff covers are the same between Non-ls and LS diffs. It was probably changed out at one point due to failed pinion bearings.