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Front end vibration when braking.

When I brake at a stop light I am getting a vibration at front end and the steering wheel shakes about half inch left/right. What can it be other than warped rotors? Anyone had this problem solved?

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Old 06-20-2020, 11:54 AM
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Loose tie rod ends, bad shocks, a tire that's delaminating (spin it and look for out of round or bulges on the sidewalls) or loose wheel bearing(s).
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Old 06-20-2020, 12:02 PM
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imho, 'warped rotors' are usually uneven glazing on the disc. this can be caused by coming to a complete stop when the pads/rotors are super hot. this will raise the carbon to the surface and the disc is harder as a result.

it is called cementite.
Old 06-21-2020, 05:11 AM
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In my experience warped rotors are rarely the problem, not saying it doesn't happen but its just rare for rotors to warp especially on a car that doesn't see the track. Also, if you are not hearing any clunking or other noises then its also unlikely to be anything mechanical like a ball joint, bushing or bearing.

First, easiest and cheapest thing to do is fully tighten each front hub nut until the brake disc cannot be rotated by hand, then slowly loosen it until the brake disc begins to rotate freely and lock it there. That ensures your wheel bearings are set correctly. Then take your car to a tire place and get your front wheels balanced, problem could be as simple as you have just thrown a weight but they will also tell you if your tires have developed any issues.

If the problem persists then start looking for mechanical failures in your bushes, bearings and ball-joints. Let us know how you get along, GL
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Last edited by 9FF; 06-21-2020 at 07:01 AM..
Old 06-21-2020, 06:59 AM
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Quote:
Originally Posted by 9FF View Post
In my experience warped rotors are rarely the problem, not saying it doesn't happen but its just rare for rotors to warp especially on a car that doesn't see the track. Also, if you are not hearing any clunking or other noises then its also unlikely to be anything mechanical like a ball joint, bushing or bearing.

First, easiest and cheapest thing to do is fully tighten each front hub nut until the brake disc cannot be rotated by hand, then slowly loosen it until the brake disc begins to rotate freely and lock it there. That ensures your wheel bearings are set correctly. Then take your car to a tire place and get your front wheels balanced, problem could be as simple as you have just thrown a weight but they will also tell you if your tires have developed any issues.

If the problem persists then start looking for mechanical failures in your bushes, bearings and ball-joints. Let us know how you get along, GL
Thanks for the tips. I will adjust the bearings tomorrow as you describe, no issues on the tires as far as I can tell, if the wheels/tires are off balance the front end should vibrate as I drive. Am I right? I have no issues driving, only when I brake.
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1984 944 N/A Passadena Gold, No Sunroof
1971 Cuda 440-6, 4 Speed, The Last 440-6 Cuda built, Black
1971 Cuda 340, A/T, Rallye Red
1970 Cuda Ragtop, 383, 4 Speed, Triple Black
Old 06-21-2020, 05:46 PM
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Quote:
Originally Posted by Thunder-71 View Post
...if the wheels/tires are off balance the front end should vibrate as I drive. Am I right? I have no issues driving, only when I brake.
Not always, most times they vibrate at only one speed range and can be at quite a high speed, depends on frequencies and stuff I’m not familiar with, but I’ve had off balance wheels not vibrate until I’ve hit over 80 mph.

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Old 06-21-2020, 06:27 PM
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