Bad rotors already?

[DDurb]

Hi gang: Have many of you had rotor problems on your 300 C's? I have a front end shimmy with moderate braking at 70mph. No pulsating at low speeds or coming to a stop.

Dealer told me the rotors are warped, and only warranteed for 12 k miles.

I have 19k. They ordered new ones, and are covering them under warranty somehow. I didnt ask as long as they are willing to do it.

This car hasn't been driven hard, or stopped hard at all. Whats up with poor performance of the rotors?

Dave

[TriSum]

Unfortunatley, one hard/sudden stop with out bringing the rotor up to temperature can cause the rotors to warp, even some of the better ones.

Originally Posted by DDurb

Hi gang: Have many of you had rotor problems on your 300 C's? I have a front end shimmy with moderate braking at 70mph. No pulsating at low speeds or coming to a stop.

Dealer told me the rotors are warped, and only warranteed for 12 k miles.

I have 19k. They ordered new ones, and are covering them under warranty somehow. I didnt ask as long as they are willing to do it.

This car hasn't been driven hard, or stopped hard at all. Whats up with poor performance of the rotors?

Dave

[vvv90]

Originally Posted by TriSum

Unfortunatley, one hard/sudden stop with out bringing the rotor up to temperature can cause the rotors to warp, even some of the better ones.

Actually the rotors are not warped. They are run out. This is due to not properly bedding the brakes immediately after purchase. You can get them resurfaced to remove the brake pad deposits unless the surface has turned to cementite which cannot be removed. If you do resurface do a proper brake bed procedure immediately thereafter.

Do a search for a member called dzeckhausen. He is the all-knowing forum member on brakes.

[Northern Rider]

Originally Posted by vvv90

Actually the rotors are not warped. They are run out. This is due to not properly bedding the brakes immediately after purchase. You can get them resurfaced to remove the brake pad deposits unless the surface has turned to cementite which cannot be removed. If you do resurface do a proper brake bed procedure immediately thereafter.

Do a search for a member called dzeckhausen. He is the all-knowing forum member on brakes.

VVV90 is right. The rotors on the 300C do not warp easily. Certainly not in normal street driving.

Here is the article on bedding in brakes. You can try this and see if it cures your pulsation from material transfer.

http://www.zeckhausen.com/bedding_in_brakes.htm

[Irwin]

Originally Posted by Northern Rider

VVV90 is right. The rotors on the 300C do not warp easily. Certainly not in normal street driving.

Here is the article on bedding in brakes. You can try this and see if it cures your pulsation from material transfer.

http://www.zeckhausen.com/bedding_in_brakes.htm

Hi NR, When I test drove my 05C (new), I noticed that the brakes just were not up to par. the dealer called me later in the day saying that the rotors were warped and they changed them and he wanted me to test drive the car. The brakes worked great and I bought the car. 11,000 miles and a little over a year later the brakes are still okay. I was told that if the wheels aren't torqued correctly then that can warp the rotors also. In PA every year the state has inspections including the brakes and I didn't have much wear.

[Northern Rider]

Originally Posted by Irwin

Hi NR, When I test drove my 05C (new), I noticed that the brakes just were not up to par. the dealer called me later in the day saying that the rotors were warped and they changed them and he wanted me to test drive the car. The brakes worked great and I bought the car. 11,000 miles and a little over a year later the brakes are still okay. I was told that if the wheels aren't torqued correctly then that can warp the rotors also. In PA every year the state has inspections including the brakes and I didn't have much wear.

That's true. Wheels need to be torqued on to spec with a proper torque wrench - not hammered on by a kid with an air gun and attitude.