C4 nubie question

I just bought my first Corvette, an '85 and have a question. When I cruise
along at 65mph or so and let up on the gas it lurches to the right for a
split second then goes back to normal. Anyone ever heard of this before? I
didn't get a chance to take the car on the expressway before I purchased it
so I only found this out when I brought it home. It 'clunks" when I shift
into drive so I'm pretty sure I'm going to need U joints and figured that
into my purchase price so I'm hoping maybe this is also causing the jump to
the right. If anyone can help or recommend a web site with info I'd
appreciate it. Thanks for any help you can provide.