Tires: Steering wheel wobble, dodge grand caravan, bridgestone weatherforce

Question
Hi Barry,
Thanks for the followup answer.  In reading my original question, I realized I wasn't as clear as I should have been.  I only get the vibration and wobble in the steering with the specific two tires that are currently on the front.  The two that are on the rear now never give me any vibration when they are on the front. It's only when the two specific tires that are on the front now is when the problem occurs.  When they go to the rear, the problem disappears.
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Followup To

Question -
Hi Barry-
I have a 2000 Dodge Grand Caravan with a set of Bridgestone Weatherforce all season radials.  I have about 24000 miles on them.  Everytime I have the tires rotated the two that currently are on the front give me an annoying wobble in the steering.  I have taken it to my Dodge dealer and to Sears where I purchased the tires to have them checked.  I have had them rotated, spin balanced and the car has been aligned at least 3 times since I purchased the tires over two years ago.  I don't put a lot of miles on the van. I am the primary driver so I definitely notice a change when these two tires are the steering tires.  The dealer found nothing wrong with the front end or wheels.  They thought the tires may have a steel belt that may have slipped.  Sears answer is just to spin balance and rotate the tires to the back.  They suggested I may have a bent rim so I took it to a shop that specializes in repairing alloy wheels.  They put it up on the rack and found no bends.  I was even back there and they showed me.  They looked straight to me too.  I guess my long winded question is this.  Is there a way to tell if one of the front tires is bad.  If so, I want Sears to prorate the price on a new set so I can get rid of this annoyance.  Thanks.

Answer -
Chris,

If every time you rotate tires the problem returns, then the problem isn't the tires.  It's the alignment wearing a pattern into the rear tires, then when you rotate those tires to the front, the pattern that is worn into the tires causes a vibration, which you feel through the steering wheel, but that pattern is eventually worn away, then you rotate tires and the pattern repeats.

So you need to look at the rear alignment.

Don't accept that "there's no adjustment", if a parameter is out, then it needs to be corrected, and sometimes that means bending something or replacing parts.  BTW, there's always a way to fix and alignment, it's just a matter of how much effort (and cost) would want to expend.

Also the alignment specs as published by the vehicle manufacturers are way too wide.  This means the you'll can get tire wear related problems at the outer reaches of the tolerance.  The acceptable tolerances are too wide by half.

Hope this helps.  

Answer
Chris,

Thanks for the clarification.

I'll bet that none of the folks who balanced the tires used a Hunter GSP9700 Road Force machine.  You should have someone look at that.

www.gsp9700.com

On the other hand, all that will do is confirm that the source of the vibration is the tires - and I think you already know that.  But perhaps this will allow to see that everything that can be done, has been done and that you'll have to live with the problem until you replace the tires.

And, no, this isn't covered under warranty due to the miles your tires have on them.  It would be a different story if the tires were new.

Hope this helps.