i just have a simple question whenever i go out on the street and spin the tires they both spin but whenever i go to the track and try and do a burnout only one wheel spins. i jacked up the car and rotated the back wheels and they both rotate the same way so i know i dont have an open diff. so what is the problem can limited slip diff's were out and is there anything i can do. thanks

 

yes, posi's will wear out. The friction discs/clutches wear out just like they do in transmissions. Never checked into a rebuilt kit for them, but the parts are out there to get it rebuilt....no a big deal actually, just takes a little free time and brake clean to get all the old sludge out of it and install new discs.

 

i gottta 3.73 mini spool rear for sale

 

i was thinking since i can spin both tires on the road. should i just skip the water box at the race track and try to do the burnout. im building up a 9" for it and dont really want to wast any money on the 10 bolt you think if i put new diff fluid in it that it would help out. thanks

 

hmm if you cant do a burnout in the waterbox, you'll probably have a harder time without the water. The street is pretty slick compared to the burnout box at a track

 

If you're building a 9" I don't know why you're worried about it, but trying some gear lube without any friction modifier will cause the clutches to grab harder.

FWIW, none of the 3rd gen posi's are rebuildable besides the cone posi in the BW 9 bolt.

 

Try these guys here. They have been building High performance rearends long before moser or currie. They built my 12 bolt over 15 years ago and its still kickin ****. They sell everything you need to rebuild a rear end.
http://www.tomsdifferentials.com/