Does anybody know what the Limited Slip additive is used for in Limited Slip rear-ends?

I believe it'* just a friction modifier that allows the clutches in the limited slip diff to grab instead of just slipping due to the gear oils lubricity.

If you wanted to know specifically what it is, I don't know the answer to that question.

LOL. Ya, I'm still pretty lost myself!! Never understood what it really does.

We need some gear heads in here!!

Okay, an LSD keeps one wheel from turning freely. Like if you had one wheel stuck on ice, and the other on dry pavement, the one on ice will spin freely.. because the power will find the easiest route out. For 1/4 mile racers, this is good for hooking up, and getting better traction, and of course, lower E.T'*. The LSD is usually a clutch pack, that decreases the free movement, but still doesn't lock up the differtial. There are some gear type LSD'*, but I think only one or two companies make them, and they are much more expensive. The clutch packs wear out eventually, if you had a '60s Pontiac with the Posi-Traction today, with 100,000 miles.. it would be shot, and pretty much worthless, hence the invention of the gear type LSD. Hope that helps, i'm sure some of the gear heads can explain it better, but that is the general concept.


-justin

I understand the concept and how it works. I want to know why the special additive is required!

Yep. I'm pretty sure the Cressida'* (*points at sig*) 4.10 LSD rear end'* clutches were just about shot. I never found out whether they were or not. The thing was a bit low on diff fluid before it was pawned off, there'd be this wicked gear whistle in 2nd gear though

... and the gear whine, not sure from the tranny or diff. That whine was to die for, almost like L67 whine

better traction.. that'* the "special additive." Better traction = lower et


-justin

I believe I answered the question in my first post. I know exactly what a LSD does and the various different types. The reason why you need an additive in a LSD is because of the clutches that are in about 90% of all LSD'*. The gear oil by itself allows the clutches to slip too much, thus keeping them from doing their job of close to equal power to both rear wheels. The additive is a friction modifier to allow the clutches to grab. The additive itself, though related to the ability of the rear wheels to get equal power, has nothing to do with traction.

One of these maybe? Amsoil makes one and Lubeguard the other.

OH!! haha I get it now. Sorry, didn't understand the question.


-justin