This was the second set I used (first were EBC that lasted under 2k miles, and they never responded to my email complaints). When I called to order them, they were very nice and used the thicker material to cut my rotors from. They were great for the first 2k, then a very slight vibration returned. Now at 7k, it is significant when I step on the brakes at speeds over 60 mph (all stops under 60 are silky smooth). When the shop put the rotors on the lathe, one side was fine, but on the other side you could see places on the rotor that were not fully contacted by the pads. Once cut, they looked perfect. Yet, when I took the car for a test drive, the steering wheel shook at any stops from 40 mph.

All very strange. I have been working on cars since I was 14 years old, and have changed more rotors, pads, shoes, etc than I can keep track of. Never had problems like this before.

 

Just returned from the shop. We put on a new set of Centric rotors-more heavy duty than the standard rotors they use. We kept the old pads because I only wanted to change one thing at a time for trouble shooting, and now the car feels perfect. The big advantage to having a shop to it and not myself-if/when they go after a few thousand miles, I have someone to complain to that is obligated to fix it.

I did check the hub thickness and runout and both were perfect.

The mechanic at the shop has been doing research calling people. Coca Cola has a fleet of HHR's and said that you can never cut the factory rotors cause they are thin to begin with. Another shop they called that specializes in brakes said they have tons of problems with HHR's and blame it on weight. The same brakes used on the lighter Cobalt are used on the heavier HHR. But, I pointed out that if there was increased load, then in addition to the rotor heating up more, the pads would wear faster which is not the case.

I am now going to check for the weight differences.

The mystery continues...

 

WOW, I love my HHR 2LT, bought it Nov of 2007 with 150 miles on it,, now I have 39K miles on it, It is totally stock except for the WeaponR Secret Weapon intake. I have rotated the stock tires front to rear once already. Probably will have to replace tires this year. As for brakes, I checked pad wear when I rotated and they're about 1/2 gone. I have noticed that slowing from 100 mph is a little iffy.. have done that only a couple times. Once though I had a noise in one rotor for the remainder of the trip after a panic stop, again it was at high speed. I consider that normal. I love DRIVING my HHR,, I know it doesn't have high performance brakes. I was ready to look at it if the noise didn't subside, but the noise went away by the next day. I don't experience any shimmy unless I try to stop quickly from say above 80 mph.
Again, I consider that no big deal.. the shimmy isn't bad, but I do notice it. When I feel that it is time to replace pads, I will get a heavy duty rotor and pad set. I really appreciate the info here on the forum.
Looking forward to the Blackhawk museum trip on the 13th...

 

This is the great mystery, which dispels the weight difference in Cobalt vs HHR theory. Some people with HHR's have no brake problems at all. Others change their rotors and the problem is forever solved. Yet some, like me, change to better rotors and pads, yet continue to get the dreaded vibration every 2,000 miles.

The braking system is really quite simple-a hub connected to a rotor surrounded by 2 brake pads. As I said before, my hub is straight and true. So why do the rotors keep getting warped???

 

After going through the same rotor problems with a 2006 Chevy Impala SS, I'm convinced that GM just cannot make a good brake rotor, or they are under-engineered so they can save 20 cents on every car they make. When the wobbles shwed up on my HHR I switched to EBC rotors with Bendix Ceramic pads, and I've had no problems so far after about 5000 miles.

 

I agree that the factory rotors suck-Coca Cola has a fleet of HHR's and a mechanic at my shop spoke to them and were told to never attempt cutting the rotors since they are thin to begin with.

I am glad that changing your rotors worked for you, but there are many of us here that have done that and only had the problem reoccur later. So while the factory rotors may not be good, why are the better quality after market rotors also going bad?

 

Is there a way to test to see if the rotors are dragging? If the tires are lifted and both tires spin the same, would that indicate the calipers are not binding?

 

I'm with bigallis1 on this one. I also went with R1 Concept rotors with EBC green pads 6K ago and they have worked flawlessly since, nary a shimmy or shake. Also show no signs of scoring or rust on the rotors.

 

I had an 06 2LT and it had the same thing. I went to the dealer and the reason is that dirt and crap builds up on the rotors and pads and unless it gets cleaned off regularly it heats things up and makes the rotors wear unevenly and warps the rotors.

There is a GM kit (a shield) that protects rotors from stuff that builds ups and will help prevent warping. Ask your dealer about it when you replace the brakes or want one installed. After the dealer did a brake job including turning the rotors it was fine.

 

Sounds too good to be true. Sadly, it does not make sense to me. Since the rotors are in constant contact with the brake pads, how can any debris build up underneath? And if anything got on the rotors, it would quickly be scraped away in one rotation of the wheel. But I will ask my Chevy parts guy and see what he says.

http://www.autogeek.net/kleenwheeldu...FUVn5QodFG_dGA

I have read ads for the wheel shields and the purpose is to keep the wheels clean-not prevent brake problems.