I notice something strange with my new LSD. This is a aftermarket helical torsen LSD.

My tranny is off the car. I did a few tests,
-I stuck the intermediate shaft into one side of the tranny and left the other side open.
-When I go to rotate the input shaft (the spline that goes into the motor), the diff rotates both sides in the same direction (that's not the strange thing),
-then I tried to see if I could hold the intermediate shaft still while still rotating the input spline, I could not. It was like the diff was locked.
-I moved the intermediate shaft to the other side of the diff and got the same results, I could not "unlock" it from the input spline. Remember the other side is open has no shaft installed.

I know on an open diff, you should be able to hold one side of the diff still while the input spline rotates. I was under the impression, you should be able to do the same on a torsen LSD if the other side has no load.

I want to be absolutely sure there is nothing wrong with this LSD before I re-install the tranny.

Is my new LSD fubarred?

Thanks.

 

depends on how much preload there is on the gears.

What brand is your LSD?

 

Hmmm...I was wondering - is the transmission in neutral or is it in gear?

Also, when I check to see if my LSD is working, I only do it when it's installed on the car already. You just put the car on jackstands, start the car up and while the wheels are spinning, you hold one side. The other side should not stop spinning. I'd say put the transmission on the car and test it. There's no reason why a brand new LSD wouldn't work, regardless of who the manufacturer is.

 

There is nothing wrong with it.

 

Thanks everyone for the quick replies. I'll just install it, drive it around the block and see what happens. If it understeers, then I'll know the LSD is permanently locked.

 

If the LSD was permanently locked, then your car wouldn't move. Helical LSD's don't lock in the sense you are referring to (they bias torque). That's the function of a Plate LSD (which works completely differently)