Truck jumping/clunking occasionally when putting in gear?

[maddog1331]

Hi all, I am new here, bear with me ok

I recently bought a 1971 chevy half ton with a 350 engine and (I think) a 350turbo trans. Occasionally it will clunk when I put it into drive or reverse, and occasionally it will lurch forward or backward when I put it into drive/reverse.

Any ideas on this? It has been years since I have done mechanic work to amount to anything (and never did anything on automatics), but am slowly getting back into it. I am not sure if this would be the universals (I did a quick check on them, couldnt tell any problem but I did not take off the drive shaft...probably should have taken it loose?), or maybe something with the torque converter?

The clunking and lurching both happen at the same time (I think...I notice this happening but don't quite remember if I have ever had one problem without the other).

Thanks for any information!