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02 Seville, 04 SRX (sold), 96 Eldorado (sold), 99 DeVille (sold)
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Discussion Starter #1
I have been turning down my rotors every 10K or so. Every time I have the service tech make sure that the caliper isn't getting stuck and that it is properly lubed. What can cause new rotors to need constant resurfacing?
 

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1926 Model T street rod, 2000 Jaguar XJ8, 1999 Corvette.
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If its just not normal wear, I would suspect restricted brake hoses to the calipers. If hose delaminates, the flakes restrict fluid flow back to the master once the pedal's released.
 

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Discussion Starter #4
I am getting a horrible vibration when braking down from highway speed. Carnut, do you think that changing the brake fluid would help? I haven't changed it and I am at 79K.
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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Which car ???

Brake fluid has nothing to do with front end vibration. If the rotors have been turned and the pads aren't worn out, you have other suspension problems. Neither car is old enough to worry about deteriorating brake lines, and they both use modern synthetic fluids, so that's out, too. Cadillac does recommend a fluid change at some mileage service interval, but that's best done by the dealer on their machines.

Jack up the front end of the car - spin each front wheel - will each turn with just a hint of drag ? That's OK. Does each wheel turn with the same feeling through 360 degrees, or is there a definite spot where the brake "grabs" ?
No undue drag and no real hard spots and it isn't the brakes.

Very, very surprised that the brake shop let you get more than one cut on a rotor: those things have a definite thickness spec - too thin a section and they're junk.

Have you ever braked SO HARD that you engaged ABS ? Get on an empty straight stretch of road and try to put the brake pedal through the firewall from about 45 mph. ABS engagement will rule that out. You'll swear the whole front of the car is coming off. Not to worry - it works.
 

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2006 STS V8 AWD, '95 Ford Ranger
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Constant wear on the brake pads can come from resting your foot on the brake pedal and riding the brakes. I've seen several people that drive with a foot on each pedal and would swear to your face that they don't do it.
 

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1926 Model T street rod, 2000 Jaguar XJ8, 1999 Corvette.
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Other than driver error, resting foot on pedal, I would verify the rear brakes are working as designed. Inoperative rear calipers could change the proportion of grip front to rear causing too much wear on front vs rear. Changing fluid is a good idea, most manufacturers recommend every 2 years. to pull accumulated moisture from the system but I see no relationship to this vibration issue. And yes, which car of yours is the culprit??
 

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I am getting a horrible vibration when braking down from highway speed.
There is a long list of simple things that can contibute to this condition.

One of the easiest to resolve is the matter of wheel lug nut torque and sequence. If you do not own a torque wrench, buy one and use it.

My method of installing wheels involves using the proper sequence to take each lug nut to 70 lb ft then repeat the process to 100 lb ft.

You wont find a technician anywhere that will take the time to do it my way. And impact wrenches are only usefull for NASCAR 18 second pit stops.
 

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I am getting a horrible vibration when braking down from highway speed. Carnut, do you think that changing the brake fluid would help? I haven't changed it and I am at 79K.
Ahh, been there. I think it is just brake pad deposits on the rotors from coming from a high speed stop and holding your foot on the brake. I had the same thing and had them turned under warranty. A year later, same thing. This time they replaced the rotors. Both times the rotors showed no signs of wear or deposits. I fully expect to have to do it again next year on my dime. Same problem on my daughters Ford Snarus just before she sold it.

Check this out. http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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...............You should post that up in CTS-V for the wusses. Good catch.
 

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Not owning one or knowing anything about them I don't go there Sub. From what I hear, it's not a nice neighborhood.
 

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02 Seville, 04 SRX (sold), 96 Eldorado (sold), 99 DeVille (sold)
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Discussion Starter #12
I am completely puzzled. I don't do a ton of highway driving and I know that being in-town can put extra wear on them. I'm not very aggressive so I don't speed up a lot jus to slow down. This is on the Seville by the way. Its not just the front, this time it is the front and last time it was the rears. I did have to replace a Raybestos set of rotors in the rear after about 4K. They got warped.

I checked the torq, all at 100lb. What I feel is the shutter vibration in the wheel, it can be felt on the passenger side as well. My tires are warn and will be replaced next week, I don't think they are the source. The front rotors have be turned down once or twice and have about 8K on them. I have also replaced both front bearings within the last 200 miles. I also wonder if it is related to the front end shimmy that happens between 60-65. I also noticed that I can really feel a slight vibration in the wheel at as little as 40 mph.
 

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If you have play in the front end, its shake can be exaggerated during braking. Before I replaced my outer tie-rod ends I got a shake during braking that could have been mistaken for TV (thickness variation of pad material deposits on the rotors).
 

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Discussion Starter #14
Replaced the left outer tie-rod end recently.The right is still the original but they said it was still good.
 

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2006 STS V8 AWD, '95 Ford Ranger
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Losing both the rotors and wheel bearings sounds to me like somebody abusing the brakes.
 

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I am guessing that you have ceramic pads? Same thing happened to me several times over. I just did a complete brake job on my car with Raybestos advanced technology rotors and Raybestos semi metallic pads. The ceramics generate a lot of heat which will cause pad transfer to the rotors. Semi metallics run much cooler.

Don
 

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This is a longshot, and I doubt it is your issue. I have a 95. I was having issues where I was 'warping' rotors every year or so. I kind of chalked it up to the age of the vehicle but I kept replacing them. Anyways, my brake booster was kind of starting to fail. For yesrs I could hear a whoosh noise every time I applied the brake pedal. I didn't think much about it because brake feel was acceptable. Eventually the booster got so bad that I replaced it. Around the time I replaced it I was about a 1.5 years into a set of rotors (which was good for me), but they were pretty warped at this poing. Long story short, I replaced the booster, which fixed the main problem of me not being able to depress the pedal. But now, after 3-4 months, my rotors have miracualously unwarped themselves.

Now, as I have come to understand it, rotors don't actually warp. What happens that, due to uneven application of the brake pads, hot spots and deposits occur on certain parts of the rotor. Overtime this leads to an uneven braking surface and pulsation when hitting the brakes. I think my failing brake booster caused me to not put even brake pressure on the rotors. At the ever least, I was proabbly doing a lot more half pressure braking which leads to overheating. Now that I can apply full pressure to the brakes, the rotors have ground down the deposits and are running smooth again.

Prior to this, I had replaced the calipers and the master cylinder, thinking it was something in the hydraulics.

Anyways, check your brake booster. Also, if your master cylinder is failing I think it could cause a similar problem. If you push the pedal to the floor, does it eventally sink down? This would be a sign that fluid is slipping past the seal in the MC.
 

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Discussion Starter #19
Thanks for the tips. I can say yes to both those posts. I do have ceramic Delco pads on the front (had them on the back and replaced them with stock ones when I replaced the rear rotors at 5K). I do hear that little "woosh" occasionally. I can't replicate it today but I know I have noticed it before. I will have the brake booster checked.
 
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