Warped rotor?

[rrcompton]

I was driving the other day down a back road going about 80mph-90mph mph and wasnt paying attention and there was a dog crossing the street so I slammed on my brakes and I felt the abs kicking in and my steering wheel shake a little bit. I really didnt think it was going to stop, I had the pedal to the ground and was trying to push it though the floorboard. :eyecrazy

The dog just sat there for a minute probably scarred out of his mind...I had to honk at him and roll down my window and yell at him for him to move. I probably sat there about a min w/ my foot still on my brakes. Do yall think I couldve warrped my front rotors in that little time w/ my foot still on the brakes?

Im asking because today Im driving on the freeway and I had to brake at 50-60mp and I got a bad shake in my steering wheel for about 2 secs. or so and I never had that problem before.

I just replace the rotors barely a month ago and dont even have 500miles on them....I find it hard to believe they warped this quick but I dont have any other thoughts. I dont have any shaking period when Im driving, even around 120mph my cars wheel is smooth as can be, its only when I brake over 60mph. I dont even have to be braking hard for the steering wheel to shake.

What do yall think??

[bimmerfiver]

Re-bed your brakes.

Re-bed your brakes.

Re-bed your brakes.

Drive 70mph
SLAM on brakes
Until car is doing 15mph
Release and keep driving car for 5 miles.

Repeat this 5x.

I just did this tonight LOL. True...my front brakes were squeaking after the BMW Meet at Bear Mountain. Why? Slight glaze on rotors. Brake pad element was worn into rotors unevenly.

Now? Brakes are back to perfect. No squeak.

Try to re-bed your brakes as it's all you can do. Next on list is to replace parts you suspect etc.

Your braking for the dog wasn't the issue. Sitting on your brakes for minutes afterwards was the issue. You may have effectively taken the bed-in process which took place when your brakes were installed and made it unven.

[Mr Hyde]

Follow what bimmerfiver said. It's just uneven pad deposition from when you were sitting still with the pads clamped down on the hot rotors. Rebedding them will solve all your problems.

[rrcompton]

I though you had to do it 5-6x then drive 10-15 mins to let the rotors cool down...like 60-70mph slam on brakes but dont lock them up, slow down to 5-10mph then back to 60-70mph slam on brakes etc. 5 times.

Anyway I'll rebed them again and see if it helps.

Thanks!!

[newton22]

Follow what bimmerfiver said. It's just uneven pad deposition from when you were sitting still with the pads clamped down on the hot rotors. Rebedding them will solve all your problems.

The reason I don't hold the brakes after coming to a hard stop. I'd stop to 0, and then just let it the brakes go (shift to neutral if an automatic).

[jamesdc4]

1 -Do yall think I couldve warrped my front rotors in that little time w/ my foot still on the brakes?

2 -Im driving on the freeway and I had to brake at 50-60mp and I got a bad shake in my steering wheel for about 2 secs. or so and I never had that problem before.

1 -Are my rotors warped? (http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml)
2 -It's suspicious.
Why does my car shimmy/ vibrate at between 45-50 mph? (http://forums.bimmerforums.com/forum/showpost.php?p=7108148&postcount=23)

[5mall5nail5]

I just left foot brake for about 1/8 mile while accelerating in like 4th or so on and off until stuff feels right. That way you don't need to be speeding and you don't need to be stopping violently.

[rrcompton]

Why does my car shimmy/ vibrate at between 45-50 mph? (http://forums.bimmerforums.com/forum/showpost.php?p=7108148&postcount=23)


Thanks for those links....I read the link above but that sounded like it was talking about just driving.

Mine doesnt make any shimmy at all unless Im braking.

I'll bed my brake pads again tomorrow and hopefully that will fix it.


I just left foot brake for about 1/8 mile while accelerating in like 4th or so on and off until stuff feels right. That way you don't need to be speeding and you don't need to be stopping violently.


That does sound alot safer.