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Deville 03
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Discussion Starter #1
While driving on the highway, if I brake at bout 60 or higher I feel major vibrations in the steering wheel! I ran my hands across the rotors which seem to b very smooth , but is that quick test not enough?? Pads are relatively new, (changed early this year) ! I was told my front wheel Hub needs to b replaced but I'm thinkin it's something along the lines of the brakes since it only vibrates horribly when brakin at high speeds! Any suggestions??? Thx
 

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White Diamond '03 DHS (with DTS floor shift)
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Re: Steering while vibrations when braking

Don't overlook the rears. Have you checked them?
I had a similar problem last year. A vibration (felt in the wheel) while braking through 40. Replaced a tire (under warranty), replaced both rotors and hub assemblies. Turned out to be the RR caliper hanging up. I would not have believed it had I not seen it for myself.
 

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1992 Fleetwood S&S Hearse, 1993 Buick Roadmaster
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567 Posts
The information below was copy-and-pasted from Hendonpub.com, in an article for Law Enforcement Publications and Conferences.



Raybestos Brake Tech School, Part One: Rotors Don't Warp
Written by PFM Staff

Brake rotors do not warp from heat, even when driven by the most aggressive traf*fic officer. Instead, they wear unevenly. This uneven wear is caused by the brake pads themselves as they intermittently touch an out-of-true rotor. The root cause of the uneven wear is one of two things: either the rotor was installed out-of-true with the hub, or the tire was improperly torqued to the hub during the last tire change.

All of this is important for fleet managers because their vehicles have the tires removed frequently and the pads and rotors replaced frequently. You won’t solve a problem caused by wear if you treat it as a problem caused by heat. Instead, fix the rotor installation or wheel lug nut torquing.

The problem of pedal vibration, incorrectly called rotor warp, occurs 3,000 to 5,000 miles after the brake or tire change. Because it is caused by uneven rotor wear, not the rotor warping like a potato chip from heat, you can’t solve this wear problem by better control of the heat, i.e., by the use of specially processed rotors or drilled and slotted rotors. Instead, you solve the wear problem by fixing the shortcuts in rotor installation or the improper lug nut tightening.

By taking a few steps, the fleet manager can easily, quickly and permanently fix the pedal pulsation problem. First, for each rotor change, verify the runout of the rotor, and then do one or two quick things to have it less than 0.002 inch, which is the OE spec for most vehicles. Two, for each tire and wheel change or rotation, torque the lugs in a star pattern using either a torque wrench or torque stick. Those two steps will virtually eliminate premature rotor wear, period.

Think about it this way: What are your conservative officers doing to their cars to “warp” the brake rotors in less than 5,000 miles? They don’t get the brakes warm (350 F), let alone patrol-hot (600 F), and never pursuit-hot (850 F). Yet their rotors are warping? No. They are not warping. They are unevenly wearing during the times of zero brake pedal pressure, and your officers are not doing anything to either prevent it or cause it.
 
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