Vibration problem at highway speeds

[Rob55]

Hello all,

I was wondering if anyone could chime in who has either the same/similar problem as I'm about to describe or if your vehicle doesn't have said problem. Basically, I have a 2010 5-door GT and when I drive at highway speeds (60-65+ MPH), I experience a regular rhythmic vibration that can be felt throughout the interior (seats, floorboard, dash, door handles, steering wheel, etc.). I've had the car for almost 2 months and it's been back to my dealer 4 times. They've balanced the front tires, the rear tires and road-force balanced all four. They even claim to have put new tires on the vehicle but I seriously doubt they actually did. I've even had the car over at my tire center and they were able to verify that 2 of the tires had pronounced "hops" on them. Currently, Mazda sent out an engineer who then reported that the problem is normal and they are refusing any further action with respect to this problem. The weird part is, we test drove 2 other comparable equipped cars from my dealership and they also exhibited the problem. I read a few posts on this forum from late last year where a couple of users here had the same/similar problem. The things is, they never posted what their resolution was. I really appreciate if anyone here could offer some info.

Thanks,

Rob

[stock3]

One thing to do would be to rotate the tires, say front to back only, not side to side, and see if the vibrations follow. I would do it myself as your dealer sounds fishy.
Tires sometimes can be faulty and no balancing will solve the problem, but if vibration is more pronounced from one area of the car, say rear passenger corner, I would rotate that wheel to the front driver's side and see if the vibration follows.

[Rob55]

That's a good suggestion. The left-rear and right-front tires were the ones that the "hop" according to my tire center. Also, they happen to be the same wheels that have sizable weights installed on the inside aspect of the wheels. I will move the left rear to the left front thus putting both wheels with the huge weights on the front of the vehicle. If the problem gets worse having both "bad" tires/wheels concentrated on the front end of the vehicle, then they'll have a hard time denying that there's something wrong.

[Default User]

usually happens when a car sits for a period of time and not move.
check the cars "birth date" compared to when you took possesson

[Rob55]

The date on the door jamb says 10/09. I took possession on 1/09/2010. This is basically what I said the service manager, that it sat somewhere for a while and developed flats spots on the tires.

[alho]

Is there anyways to fix this though?

[Rob55]

Well, once I get mine fixed, I'll certainly let everyone know. The obvious answer would seem to be a new set of tires (which they've yet to do for me). Stay tuned.