How do I know what diff I have

[Shirodori]

Hi guys, I'm having trouble understanding toyota diffs..
I had good knowledge of how nissan diffs worked as it was nice and simple but toyota.. my god.

My car is a jzx90 tourer v factory auto but converted. The plate tells me it came out with a A01C diff from factory , which I have searched and found that it is a open differential 7.5" crown.

For some reason though when I was 'testing' at my mates private pad , both wheels lit up on a stand still but yet when I try and kick the car out it wouldn't let me like an open diff.

One wheel spins freely when I jack the car up on one side, and have the other on the ground. Turn the drive shaft, both wheels turn but hold one wheel the other can turn.

I am so confused.. I am trying to figure out what sort of diff I have so I can order a 2 way unit from NST.

[Jonno2002]

toyotas old diff codes are easy like g282/f292 etc, but the newer a01c/b01a etc codes are quite confusing cause all the info on the net seems to be wrong, your diff wont be 7.5" itll be 8" being a jz powered car, the deisel and 1g models have the smaller 7.5" diff, another way to tell is the 8" diffs have 6bolt axels and the 7.5" have 4bolt, sounds like you have an open diff, with both back wheels off the ground turn 1 wheel with your hands and if the other wheel goes the opposite way then its open, if its turns the same way its lsd.... simple.

just buy a 2way thats listed for z30,a80,x9,x10 etc they all use the same internals.