mgianzero

Sorry, I said 993's, but the same phenomenon occurs with the 964's.

darth

If you're a real DIYselfer and want to spend the time to diagnose further, you may try over inflating the tires, swaping left/right, front/rear (i.e. in a mythodical manner) and note the changes, if any.

cannon1000

Bearings? My friend's truck was doing this...we removed and reseated one of his front wheel bearings and it helped a ton.

mkd944

Problem solved!!!

Since I really thought that there had to be some suspension component going bad, I decided to pull the front wheels this morning before going to work so I could inspect tie rod ends, ball joints, and A-arm bushings. I didn't see any obvious damage so I looked at the wheels and tires. That's when I noticed the outline where tape weights had previously been attached on the right front wheel. I have a spare set of wheels with tires mounted so I swapped out all 4 tires. I was inflating to the proper pressure and it occurred to me that I had never checked the pressure on my other tires. Dohh! I had already put the original tires on back on my tire trailer and it was difficult to get the tire gauge in there to check all the tires but the one that I could reach was underinflated and I suspect the others may have been also. When I drove the car with the different set of tires, the vibration was gone. So, it was either tire balance problem or tire underinflation. Those who said tire / wheel problem win.

Thanks to all who offered their advice.
Mike