I know what the manual says... but......

[roperteacher]

Can I add the LS additive to my 04. 5 American rear axle anyway??? Will it hurt anything?? THis new vibration on sharp corners while pulling sounds and feels EXACTLY like a LS rear diff that someone forgot to put in the additive. THanks in advance... .

 

[SS]

I know of several vehicles that use the friction modifier with open differentials. I suspect that it's easier to fill them all with the same fluid at the axle factory than to split them up. Go ahead - it won't hurt a thing at a 5% mix. BUT... be sure to post if it cures your chattering problem. Heck, maybe you even got a limited slip without knowing it.



Edit: I would reconsider if the manual specifically says not to add it to open diffs (though I may struggle to justify it in my own mind).

 

[Casey Balvert]

I would recommend the limited slip additive be added to the axle fluid during the break-in period. I used the recommended fluid for the first 15,000 miles and ended up with a ring and pinion failure. FWIW I really believe these axles should get 75W140 if you tow and the additive for the first 30,000 miles. Of course that is just my opinion.



Casey

 

[roperteacher]

Well, that sounds good to me!

The owners manual says that the friction modifier is NOT required, doesn't say it can't or shouldn't be used . My rear end (Ring and pinion) failed at 2200 miles. too. I'll try the friction modifier and see if that works!!