2000 Pontiac Grand Prix

Shakes or Wobbles problem
2000 Pontiac Grand Prix 6 cyl Automatic 185000 miles

My car shakes pretty bad, especially at higher speeds. When I get up to about 70, the shaking is really obnoxious, but when I let the car coast, the shaking goes away. Also, when I make a sharp turn I hear a grinding noise. And, when going at very low speeds, like in a parking lot, I sometimes hear a knocking.

The tires only have about 10,000 miles on them.

Is this a bad CV joint? If so, what am I looking at (ballpark figure) for repair costs? The car is old and I don't want to spend too much on it. However, if it is a fix for a couple of hundred bucks, then I don't mind fixing it as the car is great and I don't want to buy a new one.
January 11, 2010.

Inspect outer CV boots for tears/rips. If you see any lubricant leaking then CV axle will have to be changed.

Axles are about $70 and you would have to hang caliper out of way, disconnect lower ball joint, outer tie rod end, axle nut, to move knuckle out far enough to get axle out.

A shop would charge $300-600 for job.

Jan 11, 2010.