I just want to know what wrong with my Sure-grip (3.91), when I try to burn out and I notice my driver side and it only 3 feet long and passenger side 50 ft long. So does it worn it out or broke somewhere?

Thanks
Brad

Driver side is too heavy...
Hahahaha.........clutches are probaly worn out or its just doing its job

Could be then I will have to lose some weight!! HAHA good one.

cone sure grip or clutch sure grip?

Not sure what it suppose to be look like but my is from 1970 Roadrunner orginal

I have a 20 year old lawnmower. I live on 20 acres. The mower is all original, right down to the blade. This old piece of crap won't cut anything. Sure, I've hiy rocks, dirt and even a horseshoe once, but why doesn't it cut grass anymore?

By 1970, the SureGrip in an 8.75 differential was the Borg-Warner Spin-Resistant otherwise known as the cone type.
It is now produced by Auburn Gear.

Yours is worn out.

The cone type limited slip is officially (per the manufacturer) unrebuildable, but some have cut off the smaller end and spaced in the side gears with shims to gain some more use out of it.

You are sure to get some posts saying it's crap, others saying they have redone theirs.

Regardless, yours doesn't work now, and should be replaced with either a rebuilt Dana Powr Lock or a brand new True Trac. One preferred source is a board member, contact at www.doctordiff.com

R.