I posted this message in the 2005 sts sandbox and really soiled their new box!!

Hopefully I'm in the correct forum now...
I purchased four new Michelin HydroEdge tires. I'm experiencing sharp breakaway in the rear in some rough highway pavements. The car "Yaws" to the right then grips and snaps back. Seems as though the rear becomes airborn.

Dealer claims that nobody else has had this problem.

Dealer called Michelin distributor - also not aware of any problem..

Michelin website does not recommend the HydroEdge tire for this car.. They recommend the "energy" series or the "Pilot" series - high performance tires, which I asked for initially..

Do I have a suspension problem or a local dealer/distributor problem?

I hate it when i go in the wrong sand box !! :)

We have the same tiers on our 94 Eldo Hydro Edge have to say after 8 000 miles ,we love them have no problem with them and we drive a lot of back roads here in Florida hard,and fast ,also highway . In the rain they handle very well ..I keep the air pressure at 32 . Hope you fine out what is going on with yours .

E&H

Thanks for the reply. I'm going to take it into Costal Cadillac tomorrow and they can check the codes for the stabilitrac system.

What year is your STS? Could the rear struts be worn and not absorbing the bumps like they should?

What was the car doing with the old tires?

Sounds like my 99sts when my rear struts were bad. One was even leaking. My bet is on those. It felt like my car was rubber in the middle and the rear and front would stretch out on one side then snap back to where it was supposed to be. It was especially bad when hitting bumps on exit/entrance ramps when the wheel was turned at an angle.:thumbsup:

Four net struts later,,,,,,, all is wonderful!!