Flat Spotted Radial Tires from Car Sitting for Months?

We recently purchased a new car, it had been on the dealer's lot for a while, pictures on the dealer's website look like they were taken last Spring. Car had 57 miles on it when I drove it off the lot, so it hadn't been driven much.

I get vibration when braking, most noticed in the pedal, but some in the steering wheel as well. Vibration is most noticed when coming to a stop from 55-60 MPH or greater. Slow speed stopping, i.e. from <40 MPH almost unnoticeable. I describe the pulsation/vibration as warped rotors.

Rotors appear new, nothing visually out of place.

Dealer has had the car for a bit over 24 hours now. They claim everything brake related is in perfect working order, nothing out of spec.

The shop foreman suggest that the tires have flat spotted from sitting in one place so long, and that continuing to drive the car will "fix" the problem. Granted it has improved some, but with over 500 miles on the car now, the vibration is still quite noticeable.

The loaner car they put me in is almost identical to our new car, so identical it has the exact same problem. They claimed to have gotten yet another car that's been there a while to test drive and experienced the same issues with it too.

I'd expect to feel the vibration while driving too, not just braking if the tires truly had flat spots. There might be some vibration, but the roads all suck so bad it's hard to distinguish.

My experience with "flat spotting" has been from locking up brakes or on bias-ply/farm implements. I've had other cars with radials sit for a long time and never experienced this before.

The OEM tires in question are Continental ProContact something-something.

Should I really expect the problem to "fix" itself if I just keep driving it?

Brake pads aren't properly bedded. Take it to a back road and use the brakes. Hard. Most people don't and when driven around the lot they are either driven hard and put away wet (i.e. lot boys drive them full throttle when no one is looking and then wash them, getting rust on the rotors, etc.)

Follow one of these procedures and it should get better.

http://ebcbrakes.com/articles/how-to-bed-in-your-new-brakes-for-streeturban-driving-2/

http://www.stoptech.com/technical-support/technical-white-papers/bed-in-theory-definitions-and-procedures/brake-pad-bed-in

In reply to bigdaddylee82: Once or twice I've driven a long parked ride with radials mounted the felt lumpy. However, a few miles down the road, the lumps went away. I'd look for brake issues too, since that's when it seems to happen to you.

My Star Specs are always that way when the Miata comes out of storage in the spring. Never had the vibration last more than 20 or 30 miles, though. If you are over 500 miles it, seems likely something else is going on.

These are "Low Rolling Resistance" tires, I don't know if that would make a difference, this is the first set of LRR tires I've ever had.

Definitely sounds like a brake issue. I'd give turboswede's idea a shot.

Why have you waited so long ? ! ? ! ?

Get that car into an alignment shop right away, have them check everything from the balance to the rear end alignment.

This is a ridiculous position to find yourself in. The dealer should have stepped in already ! ! ! ! ! ! ! Anything like this would be an immediate safety issue and demands to be rectified right away, by you or the dealer.

I would try to bed in the pads, then if that doesn't work, have the dealership fix it. You bought a new car so you didn't have to deal with used car problems like braking vibrations. I think the dealership said it would fix itself because they didn't want to try to bed in the pads or replace the rotors and pads.

I'm also surprised at the lackluster customer service you guys are constantly getting at dealerships for brand new cars; makes me glad I didn't break down and buy a new car.

In reply to bigdaddylee82:I've had LRR tires before. They have issues, but that isn't one of them. Mushy handling? Soft sidewalls? Noisy and harsh riding? Yup. Vibrations? Nope. Big difference on MPG though. I lost 0.5L/100km when I ditched them.