Car wobbling while braking

Synchros shot? Weird noises while shifting? Not sure what needs to be replaced?
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rubi
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Car wobbling while braking

Post by rubi »

I checked the wheel balance and alignment, tyre pressure too. The motor mounts are fine, figure after the mechanic made sure the gear box is in place (which was one of the problems I had) and the exhaust pipes. There's also a sound when I am not moving, hanging the car on brakes on a hill for example or i donno steering. What would that be?

On a lighter note, no white smoke coming out these days and no overheating except when on high speed but it's not overheating but maybe something wrong with the sensor at high speed. Cause as soon as I brake below 90 kmh the cursor goes down to much cooler temperature.

Anyway what's with the wobbling?
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Re: Car wobbling while braking

Post by mad_finn »

Could be worn front brake disk's or possibly even worn... if you have been braking so your brakes are heated much, and hit a puddle of water wich has splashed on to brake dik cooling it much and fast the disk might have bent a bit, you can't see is it bent but when you brkae your steeringwheel and prribly whole car wobbles a bit...
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Re: Car wobbling while braking

Post by theholycow »

Disc brake rotor is warped. I had exactly the same problem recently. At first I only felt it in the vehicle shaking, it felt like I was running over bumpy pavement. Then it got worse and I felt it in the brake pedal. My passenger front brake rotor was .005 inches (.127 mm) out of true - not visible, but measurable with a digital depth gauge rigged to the brake caliper.
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Re: Car wobbling while braking

Post by RITmusic2k »

+1 Warped rotors. New rotors and pads and you'll be good as new!
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Re: Car wobbling while braking

Post by FDSpirit »

Im gonna say rotors like the others. My car is doing the same thing right now. Gotta put my new ones on this weekend.
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Re: Car wobbling while braking

Post by theholycow »

Regarding the question of getting the old ones machined or getting new ones, I'm told that getting warped rotors machined just guarantees that the problem will return because the thinner spots will dissipate heat differently and warp again.
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Re: Car wobbling while braking

Post by mad_finn »

theholycow wrote:Regarding the question of getting the old ones machined or getting new ones, I'm told that getting warped rotors machined just guarantees that the problem will return because the thinner spots will dissipate heat differently and warp again.
plus eventully they get too thin, and when you need to stop fast, and hit the brakes hard they might shatter
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Re: Car wobbling while braking

Post by FDSpirit »

Yeah, I've read really bad things about getting rotors machined/resurfaced.
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Re: Car wobbling while braking

Post by theholycow »

FDSpirit wrote:Yeah, I've read really bad things about getting rotors machined/resurfaced.
It's ok when they're not warped; if they've got grooves from the pads, and machining them doesn't bring them below spec, that's fine. The specification is there to tell you how thin is ok to reinstall them.

It's safe when they're warped, too, but the explanation I relayed above says that they'll get warped again quickly if you do.
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Re: Car wobbling while braking

Post by FDSpirit »

Ah. Gotcha. But I'd think it would be cheaper just to buy new pads and rotors.
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Re: Car wobbling while braking

Post by theholycow »

Rotors are really expensive. They're cheaper now than they've ever been but still pretty bad. You can get them machined for $10 or $15 or whatever, new ones are $40 each for cheapies. $15 vs. $80 when your rotors are still good is a pointless waste of money.
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Re: Car wobbling while braking

Post by fa22raptorf22 »

FDSpirit wrote:Yeah, I've read really bad things about getting rotors machined/resurfaced.
I cut my own on a rotor lathe each time I change the pads. Cutting the wobble out of them is quite easy actually.

Edit:
Rotors are usually good for two pad changes, and one cut. That all depends how hard you are on the brakes, and how much metal is left on the rotors.
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Re: Car wobbling while braking

Post by theholycow »

You have a brake lathe? Is that an affordable investment for a DIYer?
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Re: Car wobbling while braking

Post by watkins »

theholycow wrote:Rotors are really expensive. They're cheaper now than they've ever been but still pretty bad. You can get them machined for $10 or $15 or whatever, new ones are $40 each for cheapies. $15 vs. $80 when your rotors are still good is a pointless waste of money.
Valucrap is much cheaper, depending on the rotor. Of course nobody in their right mind would use Valuecrap, so...
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Re: Car wobbling while braking

Post by theholycow »

watkins wrote:Valucrap is much cheaper, depending on the rotor. Of course nobody in their right mind would use Valuecrap, so...
What is the actual name of Valucrap and where does one get it? I found rotors for my truck for $33 at Pep Boys and I thought that was as cheap as it was going to get.
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