Model: 2000 Bonneville SE
Mileage: 60,000
Issue: My old company car. Had Firestone FT70c put on at 35k. Dealer had a LOT of problems getting them balanced. Company guideline only allowed balance and rotation every 10-15k. At rotation, tires constantly shook at highway speeds above 70. Could not rebalance.

Just changed out for Affinity HR tires. Plus brake job (metallic pads) and computerized alignment. Dealer inflated tires to 35PSI. At speeds above 60, it'* like riding a horse.

Any one having issues trying to get their bonny properly balanced. I saw the tech bulletins, etc. I don't think it'* tie rods as it all started after the first rotation. I don't believe a bent aluminum rim would act like this, would it?

Thanks for any help.

I had an issue with this as well...exact same speed.

I took it back to the dealer and had them run a high speed balance...I was very specific on the high speed balance part.

It solved the problem for the most part. The car still feels a bit "funny" when veering slightly with the road.

Had the exact same problem. Took the advice on here and found a tire shop with a Hunter road force balancing machine (i believe it'* called). I know the model is a Hunter not sure the exact name of it. Solved ALL my vibration issues, make sure you lug nuts are torqued to 100ft/lbs too that can tend to warp the rotors if they are over tightened.