in my 88 camaro i've got a 2.8l stock with a 700R4, so theres no need for a posi rear, but i was in the shop today and i had it up on the rack and put it in drive and both wheels were spinning forward, but when the car was off and i spun one wheel the other spun the toehr way, which usually means its not posi. so whats the deal?

 

and open end will catch when in motion, posi/limited slip will catch instantly (dead stop, gas to the floor) sometimes they catch sooner, its not uncommon. iv seen people with open rears spin 2 wheels from dead stops on occasion, not uncommon. maybe you have a posi rear but its worn? you can look it up by taking the casting numbers off the axel housing. i think its on the passangers side on the front of the housing. look it up on line or in a chiltons and it will tell you the ratio and if its open or posi

 

They'll both spin the same way when the rear is in the air. It's because of the friction in the spider gears....they naturally don't want to turn.

 

in the trading post theres a guy selling differential center sections with 3 different gear ratios (one of which being 3.70, which is great) for 50 bucks. if i just pull my differential ou tand pu tthat one in will it work fine? how hard is it to do this?

 

I would think you need professional help because the dial indicators and other stuff you might need to do this gear swap is pretty spendy for a one time use.

 

so its pretty hard then? i can do all that stuff at work, if it's possible in the first place. my engines instructor is a ford tech, but im sure he could do something with this chevy rear.
what all is really involved in a swap like that?

 

Make sure he knows the procedure because I have seen Ford gears just get swapped from car to car without much work. If you use Richmond gears, you have to use their procedures and not the GM procedures. So, whose gears are you getting?