I have heard several opinions between a limited slip and a posi-trac rear end. Are there any and if so what are they?

 

the way they're spelled is the big differance

 

I thought they were the same thing, unless Posi-Trac's diff is 2-way, as opposed to 1.5-way or some other variant....

 

I've always been told they were the same. Locked in a straight line, open around the corners.

 

One and the same thing. Chevolet started using "POSI-TRAC" as trade name for the Limited Slip rear option on their Performance line up in 1955. And the name just sort of hung around over the years for any limited slip rears. Both Ford & Chrysler also had names for their limited slip options as well. Check out the RPO G80 for GMs Camaro/Firebird and it says "LIMITED SLIP".

 

Whats the difference between a 1.5 way limited slip and a 2 way limited slip?

 

I think he was just kidding about that.
As for names here are a few from different manufactures, some of the younger folk may not remember these.
Chevrolet called it posi-traction or limited slip
Pontiac called it Safe-T-Track
Chrysler called it Sure-Grip and sometimes referred to Twin-Grip
Ford also had there own name, sometimes Trac-Lock.
Anyway, just a little fun,,,,they are all the same thing for the most part, some accomplish it different ways whether it be clutches, cones, lockers etc.... Larry.

 

no there are such thing as a 1.5 and 2 way diff. i just dont know what the difference is between the two.

 

I dont have posi but either wheel will
put power to the ground, but not at the same time.
: (
Is that limited-slip?

 

no

 

what is that called then?

A one legger.

 

You have an open rear end.

 

It's called an open differential and it means only the drivers side (i think) gets traction to the ground. Do a small burn out and see which tire leaves a mark.

 

Or a really long one in the high school parking lot while the softball team is practicing...... Either one...

 

Right now Im not driving the car,
the right wheel has a wobble and the vibrations
and banging go threw to the driveshaft.


thanks for the info

 

The 1.5 and 2 way basically describes how the differential functions under power or load. A 1 way would lock when accelerating, a 2 way would lock on both acceleration and de-acceleration, and the 1.5 way is a compromise between the two where it dosnt lock as hard under de-acceleration (to help retain balance when braking at speed). By locking I mean both wheels delivering power to the ground.

When you compare this to the types of diffs used on our cars you have to look at it a different way. Unlike the imports which usually have clutch type differentials, we have a bunch of different types of differentials, each of which could act as a 1 way, 1.5 way, or 2 way depending on which type it is. We have clutch type, cone type (which is pretty much the same as clutch type), gear type, ratchet type, and locked type differentials. Because of this its kind of hard to directly compare the differentials from our car to the LSD's you'd find advertised for imports and such. We define them by which type they are, not so much by how they act. To find the best one for you, its best to find out which type would be the best for your application, and then look into how that type of differential would work under load. Most differentials for our cars are the equivalent of 1.5 and 2 way, though you could have two different "2 way" differentials that act very differently.