Brake shudder

Could someone who has suffered from warped brake rotors please tell me if the problem is there every time you use the brakes???

I am suffering from an intermittent shudder in my Forester GT which only happens occasionally (although getting more frequent).

thanking you... Phil S

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Phil S
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On a '92 Ford Aerostar I felt the shudder only when I really had to "nail" the brakes - then I could feel the pedal pulsing. With normal stops, I didn't notice it. Replaced the rotors and the problem went away.

HTH,

DJay

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Djay

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Phil S

Reply to
Andrew Danielski

My car does the same thing, it is a '99 suby legacy outback. I plane in changing the rotors myself. I was wondering is it a good brand I should look for? Also, is it cheaper to change the disks myself or have them resurfaced at a shop?

Thanks, Dan

Andrew Danielski wrote:

Reply to
Dan Chirica

I put Brembo disks (plain non-drilled) on my 95 Legacy after the OEM front discs were permanently warped. They still shudder when the disks get hot.

My guess: the wheel lugs weren't evenly torqued' - either that or that brand isn't worth the money.

Florian

Reply to
FFF

Brembos not worth the money? I'd be inclined toward the first guess.

- Greg Reed

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Greg Reed

Although the issue with lugnuts and, of course, manufacturing defects causing pedal pulsing is possible, I've read that often 'warped rotors' is a term used for improper/incomplete 'bedding in' of pads. One problem occurs if, after a hard stop with new pads, the brake pedal is held depressed allowing pad material to transfer to the newly turned (or freshly installed new) rotor such that a 'footprint' of pad material and /or bonding agent outgassed material is left in one spot. Thsi will create pulsing and is evidently best removed by some type of deep sanding or machining - again. Try searching for the 'myth of warped rotors' or some such phrase - interesting stuff.

Carl

1 Lucky Texan

Greg Reed wrote:

Reply to
Carl 1 Lucky Texan

Dan,

The OEM rotors work well. Just be sure to never, ever over-torque the lug nuts. This means using a torque wrench, a pnematic wrench with a "torque stick" is no good for this task. The factory service manual recommends tightening in 3-4 stages, in a cross pattern. By the way, the torque is listed in your owner's manual.

Also, keep the caliper slides clean and lubricated. If one of the pads is dragging on the rotor, it'll overheat and potentially warp.

Reply to
Verbs Under My Gel

My 2000 Forester with 62,000 miles are as smooth as ever. I of course seasoned the brakes and tires by taking it easy on them for a few hundred miles of progressively harder and harder stops without clamping and holding the pads against hot rotors. I have never had a problem with any of my cars and as said before my wheels are torqued to "manufactures specs" always. eddie

Reply to
Edward Hayes

```

Carl's explanation of the problem with soft (sacrificial) everyday pads leaving prints on the hot rotors makes sense. However, wouldn't almost all vehicles with automatic transmissions have this problem, since they do come to a complete stop with the brakes engaged and usually remain that way for a few moments?

The brakes on my 95 legacy (replaced with Brembo rotors) start shuddering only gradually after prolonged light braking. Therefore I tend towards the warping/ unevenly torqued wheel lugs theory in my case - it's no major problem anyway.

florian

Reply to
FFF

I'm no expert, and am just parroting what I remeber reading, but issue seems to be one with many variables; new rotor surface versus old, new/different composition pad material, pad adhesive, 'spirited' driving followed 'imediately' by 'clamping' of the brakes - lots of wiggle room here, and evidently there can even be subsurface changes to the rotor (localized 'tempering'?) that could make recurrence possible even if proper bedding is performed. All this with or without improper torquing of lugnuts. Brake systems are very much 'edge of the envelope' engineering for most cars, designers need for them to work reliably yet be inexpensive and lightweight to reduce unsprung weight. Most people don't want to sqealing but they want short stopping distances. They want then to work well in a short, sudden panic stop but have long life BUT no fade under repeated/prolonged application.

ok-found the article-interesting even if you disagree.

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Carl

1 Lucky Texan

FFF wrote:

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Carl 1 Lucky Texan

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