Anti-Slip Additive. Do I need it?????

Fuddrucker · June 12, 2003

Going to be changing the rear diff. this weekend. I did a search on here and found that some use the friction modifier additive and some don't. My manual does not specify either way. I have a 03' Chevy 2500HD with the Limited-Slip Axle 4.10 gears, and the 4L80-E tranny.

Does it need it or not??

TIA!

CanadianZ71 · June 12, 2003

JUst did my rear diff last month and the dealer told me I didn't need it. Thats probably your best bet - go to the dealer and find out for sure. I was told that unless I was hearing a chatter not to worry about it. Granted I have a different truck than you so they may tell you differently.

Rotorwrench · June 12, 2003

I've used the limited slip additive in just about everything I've had for the last twenty years. I just found out a few days ago that GM doesn't recomend it in newer truck rear ends. If they don't recomend it I wouldn't put it in. The oil they recomend probably allready has some additives in it. I've used the limited slip additive for other things than rear ends too, it can help quite a noisey power steering pump. It's probaly not recomended for that.

Wayne2 · June 13, 2003

I haven't been into the rearend of my '03 truck yet but when I changed the oil in my '02 T/A I found out it doesn't have the clutch type limited slip. I forget the name of the type it has but it doesn't need the additive. That being said I can tell you that adding the modifier won't hurt anything. If you go without it then listen for chatter when turning corners. If the rearend chatters then add only enough modifier to stop the noise for best results.

Fuddrucker · June 13, 2003

Thanks for the replys.

I am going to use Mobil 1 75W-90 and on the bottle it says "Eases gear shifting and prevents chatter in limited slip differentials." so it looks like there is some kind of additive in there already.

Wayne2 · June 13, 2003

Oh Yeah! I forgot one thing. Word has it that the new trucks come with synthetic oil in the rearends. Synthetic usually doesn't need the modifier anyway.

Fuddrucker · June 13, 2003

Oh Yeah! I forgot one thing. Word has it that the new trucks come with synthetic oil in the rearends. Synthetic usually doesn't need the modifier anyway.

Thanks.

You are correct. The rear does have synthetic in it from the factory.