I have a 1979 Camaro and I am trying to fiqure out if I have limited slip rear end. When its jacked up and I spin the wheels one goes one way and the spins the other. When I do a brake stand they both spin. I thought it was an open rear end.???

 

sounds like you got a nice surprise then huh?

 

I have read if you spin one wheel and the other spins the opposite way with the car jacked up then its an open rear end. Is this wrong then???

 

I'm pretty sure the helical (Torsen) typeLSDwill actlike an open diff if the wheels are off the ground, as far as the wheels spinning in opposite directions. I know that if one tire has no traction whatsoever (e.g. when it gets airborn for some reason) it will spin with no power transfer to the opposite wheel, so that would make sense IMO.

 

If both of your wheels have equal traction, then even without a posi they can both spin togather.

A good quick test would be to pull off the edge of the road somewhere so that you have one rear tire on the pavement and the other in the dirt, then gas it and you will find out real fast if it is posi or not!

 

With limited slip, if one tire has less traction than the other, that one will spin first, then the other will grab and both will spin together. With Posi, they will both spin at the same pace at the same time but around a corner it released enough for the outside tire to spin faster than the inside so you dont get the hop, and blow the rear... with an open rear end, only the one with no traction will spin. If you had a full locker ( spooled), then same as posi will happen in a strait line, but around a corner, it wont release and you can ruin your gears, or at the least the inside tire will turn at the same pace as the outside and wear out the rubber faster...

 

well a real easy indication would be the tag on the banjo bolts. is the car modified at all or is it mostly original? sometimes thats the easiest solution. in this case not as much but you get what im saying? if the car is an original z its prolly a posi rear, and if its a base 305 or berlinetta its prolly open, unless modified by a previous owner.my 79 was in the family since new, so i knew what was there. differentials are crazy. to me at least they are the most complicated unit on the car. i know engines well, transmissions also. but rear ends are more complex than people think.

 

Have you thought about just taking off the diff cover? Its extra work, but then youd know for sure whats in there, and it probably wouldnt hurt to change out the gear oil anyway, an often neglected part of the car...

 

I thought if you jack 1 tire off the ground, and you can spin it, it's limited.