Front Rotors warp after 7,000 miles, on one side

I have a 2007 Toyota Sienna. Back in July, 09 at 63,000 miles I had the brakes replaced, the back rotors replaced and the fronts rotors turned. After 6 weeks or around 7,000 miles, the pulsing started again as if the front rotors were warped. I brought the car in and had new rotors put on the front, thinking that turning them was a bad idea. That as in Sept 09. Since then the sienna as been back to the shop twice, once in November 09 and again in January 10, with the same rotor warping problem. Each time there was about 6,000 miles on the rotors, it was found that the passenger side rotors were the ones that were warped. The shop each time put new rotors on as part of the warrenty.

Any ideas why this keeps happening, the shop has no idea why this is hapening and the way the car has been driven has not changed from the first 62,000 miles where we did not see this issue.

Any help would be great.

Most brake rotors are made from cast iron. Today, most cast iron is made from scrap and the rotors themselves are made in low-wage foreign countries…

This board sees many threads dealing with warped rotors, so I would say it’s a common problem. Perhaps the shop you are dealing with needs to change suppliers…

Since it is the same location each time, I would suspect that the caliper is not sliding freely or that the caliper piston(s) is sticking. I would have thought that they would have replaced the caliper by the second or third time you came back in with this problem.
If you have a point-n-shoot type thermometer, you can measure the rotor temperatures on each side and see if the passenger side one is hotter than the driver’s side. That would support it being a caliper issue.

Maybe the problem is not the brake rotor at all. Maybe it’s a loose wheel bearing, tie rod, tie rod end, etc. which can mimic a warped rotor.

As to why it’s fine for a while before this occurs there is an answer for that. A rotor may warp a bit after some use and this can be normal (say .002 of an inch) if the warpage is not excessive. It may not even be noticeable.
However, if there is any looseness in a wheel bearing or suspension component then this small amount of warpage can be magnified and made to feel worse than it actually is.

There really should be no guesswork on this. If they’re constantly machining and replacing rotors due the diagnosis of warpage based on symptoms only instead of actually checking this with a dial indicator, micrometers, etc. then they’re going about this all wrong in my opinion.

If the warped rotor is in the same location always, you probably have a right front caliper that is slow or not releasing, or a left front caliper is not applying. In either case the right front wheel would be clearly hotter than the left.

I Think You’ve Received Some Really Good Advice.

OK4450’s observation that if they haven’t specifically checked each rotor that comes off then they’re just making assumptions, throwing parts at the problem.

Tardis mentions using a “point-n-shoot type thermometer”. I have one of these infrared non-contact thermometers and have used it successfully to diagnose this exact situation. The beauty of it is that you don’t even have to take anything apart. You’d need to drive the car for a few miles and then coast down to almost stopped before touching the brakes to come to a stand still, so as not to heat both rotors to a high temperature, first.


Thanks everyone for your input, this really helped. I waiting for this to show up again, when it does I am going to take your suggestions to my repair shop.

One thing to add, they did see when the rotor was warped it was only out a little bit. But when you are on the highway and trying to breake the shaking was huge. So now I am wondering based on your comments if it is a bearing thing and not a caliper issue.