[450xDaD]

My wife had the SAME problem on her '07 Quest. The thing had the same "death wobble" which we discovered with 250 miles on the odometer. It was the most bizzare thing. At 70 it was fine, hit 73mph it started, 75-78 it was unbearable, 80 mph it went away...smooth as silk. What made it bizarre was that the steering wheel didn't shake, but the seats did...violently.

We took it to the dealer, and they replaced 3 tires. They said they were out of spec or something to that effect. Took it home, and same thing happened. Not any better.

Took it back AGAIN(2nd time). They road force balanced the 4 tires again. Took it home, and was disappointed to find the problem still there. this time it wasn't as bad, but still...it was there. I was starting tthink I was crazy.

Finally, 1500 miles I couldn't take it anymore. I was thinking Florida Lemon Law (3 strikes you're out). I went back and asked to drive another vehicle with the same specs as mine. I also asked the Sales Manager to come along to prove I wasn't crazy. I Drove down a good stretch of highway between 70-80, and low and behold...NO SHAKE.

We then took our van, down the same stretch of highway, same speeds. Just as expected it shook like a bee-otch. He was amazed how bad it was.

We got back, and he told the service manager to swap tires from van to van. The thing has been perfect since.

Moral of the story....as someone mentioned in a previous post, road force balancing means diddly-squat. You could just have bad luck with those crap-year tires like we did. I bet it's in the tires........