Still having tire problems

[fullthrottle52]

ByPro,
I have 18 in rims. Stock rims. The Bridgestone were 17 in wheels and tires off a 2001 Boxster. If I would not have swapped them out I would say it is mechanical but after driving those wheels and tires I have to say it is associated with one or the other. I am currently looking to find a local 986 boxster that would be willing to try a swap and drive. That would tell me alot. Just had the boxster out again to go to the store and pretty smooth up to 50 or 55 mph. Once I get to 60 and above it starts and gets progressively worse with speed. When I get to 75 the whole car is shaking.

Not fun to drive at highway speeds where you spend a lot of time.

[Johnny Danger]

What type of balancing did they do ?

[fullthrottle52]

Johnny,

The latest balance on the Michelins was a regular balance maching. The previous tires were balanced at a different company with a road force balance machine. The reading from the road force balance machine were all within specs. The rims showed no wobble or high spots.
That is the difficult part to narrow down.

[Johnny Danger]

Originally Posted by fullthrottle52

Johnny,

The latest balance on the Michelins was a regular balance maching. The previous tires were balanced at a different company with a road force balance machine. The reading from the road force balance machine were all within specs. The rims showed no wobble or high spots.
That is the difficult part to narrow down.

What were the actual specs ?

[fullthrottle52]

I did not bring them home with me. They had a print our and said they see no signs of bent rims or a out of round rim.

[Hootie]

My 01 has a similar problem but to a lesser degree. I've only had it 6 months and it's not that bad, but I know the previous owner went through some tire and wheel changes, probably in a vain effort to smooth it out. I haven't dealt with it yet, fearing need of a front end rebuild... interested in your outcome.

[Johnny Danger]

Originally Posted by fullthrottle52

I did not bring them home with me. They had a print our and said they see no signs of bent rims or a out of round rim.

Unless they were able to road force balance them down into the mid or lower teens, or better yet single digits, the end result accomplishes nothing . Any figures higher than that typically means that you have a tire(s) that is out of spec. It's not uncommon for a brand new, low profile tire to be out of round. I've dealt with this issue myself. In any case, assuming that your "indy" has ruled out any suspension related problems, the only thing that I can think of is that there's a problem with something not being hubcentric with regard to the wheels . The wheels are in fact oem, correct ? Again, no spacers ?