2G GSX AWD Transmission, Transfer case, rear end, does this sound right?

[Trelisong]

I wanted to verify that my LSD rear end was working. I had no reason to think it wasn't but since I had all four corners up on blocks to do the brakes I figured why not.

I started the car up and put it in 1st gear. all 4 corners were spinning. I tried to apply some light resistance/drag to the rear wheels and could not slow them down or stop them, they kept on a spinning.

I was however able to stop both sides of the front from spinning with just my finger tips... is this normal behavior for the GSX AWD drivetrain?

Don't get me wrong, I have done a lot of work on the engine. but I have never had the tranny apart and do not exactly know the way that it is supposed to behave for the front wheels.

 

[delta448]

Unless you put an aftermarket LSD device in the front diff of the car, that's exactly the way it should be.

Your front diff is open, meaning the side with least resistance spins fastest, if you have the car in the air in neutral and spin one side of the front, the other front will rotate in the opposite direction. With the car in the air and in gear, you can stop one wheel from spinning but notice that the other front wheel will now spin significantly faster since all the output torque is now going only through the other side of the diff.

The center diff is a viscous type LSD that attempts to match the averaged speed of the two fronts with the input for the rear diff.

The rear diff in your case being a LSD will allow a small amount of speed difference between rear wheels when it encounters enough resistance, (you're probably not going to be able to do it with your hands without inflicting some serious pain) but in very short order the slip limiting device should firmly lock both wheels to nearly the same output speed.

This is why guys with powerful GSTs should at least consider a insert for the front diff of their car, spinning the crap out of one front wheel gets old quick and can be dangerous.

This article has about 9 different pages, but has some really good explanations and some cool animations to show how different types of differentials work: HowStuffWorks "How Differentials Work"