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2003 Deville
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25 Posts
Discussion Starter #1
I have a shaking or vibration when applying the brakes from a moderate to high speed. The front brakes were done by the dealer 2 - 3 years ago but only 7 or 8 thousand miles, maybe less put on the car since then. The dealer says warped rotors are causing the vibration which means they probably didn't turn them when they did the brakes.

Is it better to replace the rotors or can I have them turned, assuming they have never been turned and if they have that there is enough left to turn? It seems I read somewhere that it is better to just replace them on a cadillac but I can't find that thread so don't know if I read that or not.

Any issue's with O'rielly or Autozone rotors? I did read on this forum that all rotors are made in China. Probably at the same plant...

What about the pads? There should be alot of pad left (haven't looked yet), if so is it alright to reuse them or might warped rotors have damaged them in some way that is not easily visible?

Thank you for any and all advice. This is my folks car and I want to do it right (unlike the Cadillac dealership)

Brian
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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Passenger car - and most other - rotors are cast and machined from gray iron. It does not warp.

Rotors can be skimmed to remove surface irregularities and brake pad resin deposits, or you can look through any of several aftermarket brake manufacturer sites to find a suitable set of daily driver rotors and pads (usually ceramic) that will give strong, reliable, smooth, quiet service.

Look at www.rockauto.com and www.placeforbrakes.com.

Study the Tech Tips for how-to information - there are several specialized procedures you must follow for these cars - like screwing in the rear caliper pistons.

ALL hub, wheel and rotor mounting surfaces must be absolutely clean and true. No loose/worn front suspension parts/bushings. Lug nuts torqued to 100 lb/ft sequentially in a star pattern.

For brake rotor construction, breakin and care - study the tech papers in the Automotive sections of www.ebcbrakes.com and http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths . Both companies are HUGE brake disc manufacturers.
 

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2010 DTS
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87,306 Posts
Rotors are made of cast iron. They don't warp. http://www.hendonpub.com/resources/article_archive/results/details?id=1787 You probably just have a pad material build up on them. You MIGHT solve the problem by a couple of hard brake applications, but DO NOT come to a stop or just drive for a 1/2 mile or so while lightly applying the brake to heat and clean the rotor.

Turning may be an option, but I just replaced a set on my daughters car because when I checked the numbers, there was only .006 between the serviceable number and the discard number. I just replaced them.

As you said, rotors are all made in China. This is one case where I would not hesitate to use an AZ part. Right or wrong, I don't put O'Rielly in the same boat as AZ.

If there is a lot of pad left, go ahead and reuse them. They are NOT damaged. Personally, I'd use over 50% as a criteria.
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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From the 2002 Seville GM service manuals:

NOTE: Whenever the rotor has been separated from the wheel bearing flange, clean any rust or contaminants from the wheel bearing flange and the brake rotor mating surfaces. Failure to do this may result in increased lateral runout of the brake rotor and brake pulsation. (In this case, "lateral runout" is vibration.)

See also GM/Cadillac TSB #01-05-23-001B of 01/31/2008
 

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2003 Deville
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25 Posts
Discussion Starter #5
Submariner and Ranger, thanks for the quick responses.

This has been an ongoing problem, I have just never gotten around to doing anything about it. I will have the rotors turned to clean them up if the specs are ok.

The shake is pretty violent and the front end checks out ok according to the dealer and the car drives and rides fine (who of course told me the rotors were warped but apparently that can't happen so I guess they just wanted to sell my folks rotors...), is it possible a caliper could be sticking or would that cause a different problem?

Brian
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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Stuck front caliper(s) on these cars is rare. Better bet is a torn front center motor mount along with wear on the several other engine and cadle mounts as well as worn/loose front sway bar links and mounting bushings.

ANY slop in any of those powertrain mounts is an invitation to vibrations.

Don't overlook tires that have broken radial belts or tread misalignment.

Last resort, after rubber mount checks and hub/rotor/wheel cleaning and alignment checks, is a Hunter Road Force wheel balance procedure.

Bottom line: These cars are hypersensitive to front end - powertrain - mounting and alignment faults.

EDIT: Front center motor mount - covered in here and Tech Tips a million times - Get a trusted assistant, open the hood. Start the engine at idle. You stand next to the driver's side fender, looking at the engine/radiator relationship. Have your assistant firmly hold the service brakes with the left foot, place the stick in D and accelerate the engine to 1200 rpm or so. If the engine torques - rotates - more than 1" toward the firewall the front center mount is toast. Replacement is a mechanical aptitude test .............
 

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2010 DTS
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Here is something else to consider. Admittedly, this is Not common, but I recently had a vibration in the front end (I could feel it in the steering wheel). It was between 38 and 40 MPH give or take a MPH or two. Tried everything, brakes, rotors, hubs & tires. Believe it or not (I had a hard time believing it) it was a hung RR caliper. Replaced the calipers and all is well.
 

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1991 Cadillac Brougham D'Elegance 5.7 Litre, 1994 DeVille
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The most common problem for what you described is the rotors. For the cost of them just replace them and go from there. If they look smooth you can get away without replacing the pads like Ranger said, if they have grooves worn in them at all replace the pads too. For the cost of pads I always replace them with the rotors if they're needed or not.

The dealer isn't trying to sell you anything by saying it's warped rotors other then trying to fix the problem. Whether it can happen or not that's the most common name for that problem because of the way it feels. If they tell you the problem is dirty rotors you'd instinctively think why don't just clean them instead of trying to sell me the new part. Usually if a front caliper is sticking the car will try to pull to one side.
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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In many - if not all - cases, "dirty" rotors can be cleaned of deposits and winter rust by performing several aggressive stops from 55 - 60 mph, driving away immediately after each stop and finally letting the rotors cool for 2 - 3 miles of normal driving after the cleanup stops. This procedure will get the rotors HOT - not to worry - those rotors are designed to run cherry red during aggressive road course work. That's one reason they're made of cast iron.

Hot rotors ??? Common.

https://www.google.com/search?q=night+time+racing+brake+rotor+pictures&tbm=isch&tbo=u&source=univ&sa=X&ei=Ay_SVJrKG4erNsiZgMAH&ved=0CCIQsAQ&biw=1366&bih=618
 

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1998 Deville
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710 Posts
Mine had the exact same problem even after replacing the front rotors. Bad shake you could feel in the front. Turned out it was the REAR rotors. So replace them first.
 

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2003 Deville
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Discussion Starter #11
Took the rotors to turn but couldn't. One was marginal but the other was under the minimum and I could feel very slight grooving on both with a finger nail like they hadn't been turned when the dealership did the brakes a few thousand miles ago... That was interesting to me, seems they would have sold my folks some overpriced replacements. I don't know but I don't see how the pads could wear the rotor down below minimal specs. Hard to find trust worthy shops.

The pads had minimal wear so replaced the rotors and went for a drive. Problem seems to be resolved. Thanks for all the help.

Brian
 

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2002.5 F55 CORSA STS, 2014 Explorer XLT FWD
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Just like brake shoes and drums, it all wears out as it's designed to do. Rotors are NOT forever - by any means. Normal maintenance items.

That's why, for every mile you drive, you put $0.29 in the bank to pay for car ownership costs.
 

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1992 DeVille, 2013 ATS 3.6
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Submariner409 said:
Just like brake shoes and drums, it all wears out as it's designed to do. Rotors are NOT forever - by any means. Normal maintenance items. That's why, for every mile you drive, you put $0.29 in the bank to pay for car ownership costs.
Hahahahah this is great
 

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1998 Deville
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Took the rotors to turn but couldn't. One was marginal but the other was under the minimum and I could feel very slight grooving on both with a finger nail like they hadn't been turned when the dealership did the brakes a few thousand miles ago... That was interesting to me, seems they would have sold my folks some overpriced replacements. I don't know but I don't see how the pads could wear the rotor down below minimal specs. Hard to find trust worthy shops.

The pads had minimal wear so replaced the rotors and went for a drive. Problem seems to be resolved. Thanks for all the help.

Brian
Rotors are so cheap I don't know why anyone even bothers anymore to turn them. Waste of time and money.
 
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