Drive shaft U-joint(s), almost certainly. Go to your nearest Monro Muffler shop; they don't fleece you too bad... It's a $15 dollar part (they'll charge you ~$40 for the part) plus labor. I'd do 'em both, even if one seems OK.

Shouldn't be more than ~$200 if that's the problem...

If you can turn a wrench, you can remove the drive shaft yourself (just remove the U-joint "straps", 4 screws, & pull/slide the shaft out on the slip joint side) & carry it into an axle shop (check the yellow pages). They should do the job for less than half that.

Good luck, MarkH

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