The vibration has no pattern, but is felt by anyone driving the car above 68 MPH. It feels like it is mostly the front, although it is felt somewhat through the seat. The front upper strut mounts have been replaced, as well as the tires. The right side wheels had quite a bit of curb rash, so I had them rebuilt to new condition. I have taken the car to the local Goodyear dealer numerous times to have the tires re-balanced. The last time they found that a weight had slung off, but the vibration remains.


Any ideas or experiences are appreciated.

 

Bushings and Ball joints go out on these cars and will create this type of issue, Even if you try wiggling them you won't know. Some get kits to replace them, some use rubber other polly.

 

Probably still wheel balance. I have had to resort to the Hunter Road force Balancer at Discount Tire to fix mine. One wheel never did correct completely, had to replace it.

 

I bought my XK8 used. The car had a vibration that started around 70 mph. The dealer I bought the car from said he had the the wheels re-balanced and they could not get the vibration out. His mechanics told him they thought there was something seriously wrong with the car. He personally thought it was the tires. I took a mechanic with me when I went to buy it and we went over the car pretty thorough. We didnt feel like it was anything serious.

After buying the car I took it to where I get my tires. These guys do nothing but tires and suspension. They have one of those Hunter machines. It wound up being the back right wheel. They balanced and re-weighted it and no vibration at all at well over 100 mph.

 

I also had this problem vibration between 68MPH and 78MPH it went away above 80MPH. I tried balancing the tires even road force balance, I even replaced one rear tire that was questionable. The problem would not go away.

This year I needed brakes and got new front rotors, poof the problem is gone! I hope it doesn't come back.