Hello

It sounds like you've covered all the front-end issues which cause vibration but I will add some others not mentioned.

• check wheel balancing, front and rear
• check for cracked or bent wheels

The two items were probably looked at before but they are the most common problems associated with vibration.

Another place to look is the transmission, if the torque convertor is not balanced properly it will set up a vibration at the speeds mentioned. There are other engine components like pulleys etc. that will also vibrate if loose or defective.

You should have this vehicle taken to a shop and have them place it on a lift and run it at various speeds to detect the vibration. It may be necessary while on the lift to jack up the lower control arms "just a little bit" to keep the axles even when performing this check. A trained professional should do this to avoid personal injury. The person doing the work has to take an interest in the problem to really find the "problem". It may be necessary to road test the vehicle with the technician to point out exactly when the vibration comes in. I have found this approach to help a lot. It gives the person performing the work a better idea of what the customer is concerned about.

I have found vibrations in the past that were not related to wheels or tires. The other things mentioned came into play, It takes time and patience to detect this but I truly know hopw frustrating this can be.

Dan