Question with Gears?

[martfr2]

I am looking to by an 88LX and I drove one today that looked really good and price was great. Some of the things I noticed were when I was driving the car it knocked from the DIFF. It actually sounded as if the gears were loose in there. When I would roll it out of a stop sign there it hit. When I shifted to 3rd bang again it would hit. I know this is hard to explain but can it be that the gears are loose in there? I know this car has 3:73s and a Tremec 3550, I have been driving stick for about 15 yrs so I know its not user error! LOL I have had my 95 with 3:55s for about 6 yrs and I have never come across something so weird like this. Anyone have any ideas what might be happening? I kinda wanna by the car but cuz of the tranny but it might be too jacked up. Advise please.
Thanks guys

 

[94 DropTop]

Could be the bushings in the ears of the diff. Mine does somthing just like that, and i have aftermarket uppers and stock 164k bushings

 

[CC'S95GT]

to ck the gears jack the rear and leave one wheel on the ground( or have a helper hold the other tire) and try to rotate the tire in the air you should get some play but not an excessive amount. may be the drive shaft u-joints too. these are just other things to ck for while you are under there

 

[95-stang]

As above, check the shaft uj's, it could even be a loose pinion nut.

 

[ddrracing]

My guess would be U joints. It pretty typical, and i usually automatically replace them on every car i buy, cause you never know if the guy before you did.

 

[martfr2]

Thanks for the help guys...Ill check that out!