I have a 1991 z28 with a 350 and 5-spd. Currently I have an Auburn Posi w/ 3.73 gears (Z rated 255 50R16 tires). In straight lines the posi works great, but in corners, especially when it is wet and I romp on it, it will just light up the pass rear tire. Also when backing up on a hill, the driver tire tire left the ground and then it just started spinning to where I had to get a running start to make it over the hill. So left turns and slides are decent usually, but they dont work so good to the right.

1. Is my posi just worn out, and if so is it rebuildable? (Im not sure if it is a torsen style to where this is just normal operation???)
2. What posi should I replace it with that will work better? This is my daily driver, but I like to auto-X on weekends, and I love power sliding all the time I'd like one that I could slide as well to the right as to the left.