Shaking over 70 mph, soooo confused

[97 Boxster]

Originally Posted by fullthrottle52

Check over on the general discussions section and do a search for "tire problems".
I posted a similar problem recently and chased the monkey for 4 months. I was just about to buy new rims for the front (tire place told me I had bent rims) when I took the car to a tire store with a road force balancer. They gave me back my car in less than an hour and it ran really smooth. The also found a new tire on the rear that had a high spot in it (Michelin Pilot Sports). Replaced and now all the vibration is gone. Drives smooth as silk.
P.S. I ask the guy who did the balance what he did to make the shakes go away. He just smiled at me and said "I'm just damn good at what I do". End of questions. I just drove it home with a big smile on my face.

FT 52 - Thats basically the same response I had today. I told them I wouldnt pay until they could find the problem. He said it was simple, I noticed you had cheap directional tires and after inspecting all the suspension components it was a simple solution - put some good tires on and check it out. By checking it out he made me take him on the highway to 85-90 with NO VIBES. Thats one confident guy.