rear diff

I just put in a New rear diff. in my '87 cuz ever time i let off the gas there was a bang and a pull( like it was conected to something) at the rear of the car at the same time. so i changed it what could be the problem my big brother said he change the bolts on the rear tire in the driver side could that be the reson if they are to loss? i need to get the car fixed so i can drive it like i uesd to. You know there is no other feeling then the rx-7, it has been bothering me for long time what is the problem?

Re-write your problem because it is hard to understand.

Did you put the diff mount back on on the front snout? I had the same problem with the clunking and unstable feel and it was from a broke mount.