Replace or resurface warped brake rotors?

[Jimmy9190]

I had Tires Plus replace the front brake pads and rotors on my Dakota at about 60,000 miles. Now at 118,000 there is a vibration/shudder/pulsation from the front end as I slow down from about 40 mph to a stop. I am sure the rotors are warped.

Last time I rotated my tires I saw that I had plenty of pad left. The pads have held up well but I don't know what kind of quality parts the Tires Plus rotors are. I have not had the time yet to remove the wheels and check the rotor thickness, but if there is sufficient thickness left, a tire shop down the street will turn them for me for $18.00 each.

Question is, is it worth it to turn rotors or will I be have the same problem again, say in another 20 or 30K? I am tempted just to buy new rotors and pads too and be done with it. I will use Napa parts, I can do the whole job for about $85.00. Premium parts are not in the budget but I need to fix this problem before it gets worse.

So I don't need to throw good money after bad. I recently read that rotors will wear out faster after they have been turned. Any ideas/info is greatly appreciated here.

 

[marc1]

Turning the rotors removes metal and makes the rotor very susceptible to warping when heated (braking). I think it's pretty much a given to not turn rotors anymore. I sure don't. Watch the quality of the new rotor... don't buy the cheapest one... it's cheap for a reason.

 

[SLJ2137694]

Brake pulsation is caused by thickness variation in the rotor machined surfaces. Thickness variation is caused by run-out in the rotor when it is mounted. Run-out is caused by dirt/rust between the rotor and hub mounting surfaces, incorrect or un-even wheel nut torque, run-out on hub surfact, etc, anything that causes a rotor to not run true. When a rotor is installed with run-out, everytime the rotor turns a little metal is worn off the high spots on the rotor by the brake pads and you end up with a thickness variation in that spot. If you are friendly with someone at a GM dealership ask them to print off for you the indepth service bulletin that addresses this issue and gives the correction procedures. Most people who say their rotors are warped really don't know the root of the problem and these is alot of mis-understanding on this subject. During my career at General Motors I had responsibility for brakes for 20+ years. You can re-surface or replace rotors but if you don't fix the cause of the run-out the problem will be back.

 

[ARCOgraphite]

Usually proper re-torquing the wheels at reinstall (by HAND with a torque wrench) will fix your warp. Otherwise - make a diagonal saw cut from the edge to the center, so when the unit heats and expands its doesnt curl. Im not a fan of turning "warped" rotors, in fact, I'm not a fan of turning rotors at all - and I used to do tens a month in the 80's.

 

[Familyguy]

Originally Posted By: ARCOgraphite
Usually proper re-torquing the wheels at reinstall (by HAND with a torque wrench) will fix your warp. Otherwise - make a diagonal saw cut from the edge to the center, so when the unit heats and expands its doesnt curl. Im not a fan of turning "warped" rotors, in fact, I'm not a fan of turning rotors at all - and I used to do tens a month in the 80's.


No. A proper torque from the get-go can head off the problem, but once it's there, you're hosed. Replace the rotors. It just isn't worth the hassle to cut them and brand new parts won't cost much more.

 

[drive4show]

New front brake rotors can be found for about $18-20 for my FWD passenger car. So paying $18 for resurfacing just doesn't make sense.

As far as quality, blank rotors from Kragen or AutoZone are just fine, based on personal experience after reading BITOG-like car forums.

Good luck!

 

[Jimmy9190]

Thanks for the help. I'll get a new set of Napa premium rotors, about $33.00 each and probably replace the pads while I'm at it. The pads "look" OK, but I'd rather just do this job once and be done for a while. If I used the existing pads, I'll just have to replace them again soon too, so I may as well do it all at once. I put a set of $26.00 Napa True Stop pads on my gf's Accord and have had no problems with them at all, and no brake dust either. The pads the tire store used have caused a LOT of dust on my wheels.

I think it's just better to replace the rotors too, after reading here and online. I guess that's why places like AZ and AAP don't turn rotors any more. Why turn them when for only 10 or 12 dollars more you can get new ones?

I'll clean and adjust the rears too and hopefully my brake issues will be done for a while. I also hear that the rear brakes on a Dakota are too small for a 3000 pound truck, and that wears the front brakes out prematurely too.

Thanks again for the help here.

 

[03cvpi]

Just remember to use a torque wrench on the lugs nuts and torque to the factory spec. And make sure the mounting area for the rotors is free of rust or debris.

 

[stranger706]

I've always been told to get the best pads and cheapest rotors.

Im no brake expert. Any merit to this?

 

[SteveSRT8]

somewhat true, but brake pads come in a zillion flavors.

Read this link and learn that rotors almost never warp!


http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml

I also believe in simple replacement. Rotors are surprisingly cheap if you shop a bit. And machining only introduces the chance of a [censored] lathe job.

 

[mechtech2]

AT almost 60k on the brakes, you are due for new parts!
The main reason I don't like cutting rotors is costs.
It used to be cheap, and now is expensive. And the finish can be all over the place.
Who knows how carefully they mounted the disc to the machine? This can actually cut in a wobbilation.
So new cheap rotors are my general advice. Clean them with brake cleaner and soap and water first. Take the 10 minutes to do this!
But use good pads!
Make sure the calipers are free and well lubed.
Torque the wheels with a torque wrench. Too loose or too tight is not the problem, uneveness is.
Go ahead and bleed the system while you are at it.

 

[demarpaint]

When you guys replace front rotors on RWD cars do you change out the wheel bearings and races too? Lets say they had 60K miles on them. A discussion we had the other day, I figured I'd ask here. I'm not a fan of cutting rotors either.

TIA

 

[George7941]

Originally Posted By: demarpaint
When you guys replace front rotors on RWD cars do you change out the wheel bearings and races too? Lets say they had 60K miles on them. A discussion we had the other day, I figured I'd ask here. I'm not a fan of cutting rotors either.

TIA


I don't replace the bearings but I do take them out, flush out the old grease with a bearing packer, repack them with fresh grease and install a new grease seal. With contaminants removed, the bearings will last almost indefinitely.

To clean out the bearings properly amd repack them is a bit tedious but worth doing, especially on your own vehicle.

 

[ksJoe]

Originally Posted By: mechtech2
AT almost 60k on the brakes, you are due for new parts!


Really?

My wife's Vue is at about 109-110 k miles and still has original pads, shoes, and rotors. When I checked a couple months ago, it still had at least 4mm on the pads/shoes all around. I've already got the new pads & shoes, and I'm planning on doing them around 125k even though they won't be down to 1mm by then. It has a slight shudder when moderately braking at speed. But its been that way for most of its life.

 

[Familyguy]

Originally Posted By: demarpaint
When you guys replace front rotors on RWD cars do you change out the wheel bearings and races too? Lets say they had 60K miles on them. A discussion we had the other day, I figured I'd ask here. I'm not a fan of cutting rotors either.

TIA


Back in the day (Tm), I'd check and repack the bearings. These days, they're mostly sealed bearings so there isn't a whole lot to do unless you think it's starting to go south (in which case you just replace it).

 

[Jimmy9190]

Well I guess it's my time to vent. I didn't get started on this until after 1pm today. I went to Napa and bought a container of brake fluid, rotors and pads. Rather, I paid for all this at the Napa store. I had to drive to another Napa 10 miles away because my local Napa only had one rotor in stock. No big deal, it was a nice sunny warm day here and I enjoyed the drive. Then I ran around town looking at torque wrenches at AZ and Walmart. AAP didn't have one on their shelf for some reason and the counter was crowded with customers so I went to Burger King, had lunch then to Walmart and bought what looks like a pretty decent click style torque wrench for $25.00. The same wrench at AZ was another $5.00 so I thought it was a good deal.

Anyway I took my time about getting the truck up on jack stands in the garage, finally got started about 3:30. Working on the driver's side first I cleaned everything off with brake cleaner, checked the original rotor for about 10 minutes. Near as I can tell, it is warped, has anywhere from .003 to .009 difference in thickness at numerous points all around it. I don't own a micrometer, just a digital caliper. My Haynes book says .004 is the maximum acceptable difference. Anyway, I coated all 4 new pads with CRC anti squeal compound, let them dry for 10 or 15 minutes. Meanwhile I cleaned the hub mounting area for the new rotor, cleaned the caliper and slide pins very well. Then when I went to put the new pads into the caliper, guess what- these ones from Napa are not the correct pads for my truck. There is a spring arm coming off the mounting plate on the outer pad that my old pads don't have. None of the pads pictured on the Napa, AAP or AZ web sites have that spring arm pictured either..But these pads do and the mounting brackets on the new outer pads are not in the right position either. Funny thing is the pictures in my Haynes book show that spring arm, so there has to be some Dodge truck that uses that pad.

I live in a little town in central Florida and my local Napa closed at 4pm today. So did the one where I had to go to get the rotors. Neither one is open on Sunday, either. There is another Napa store about 20 miles north of here, I think that one is open on Sundays and am hoping they will be willing to exchange the pads for me tomorrow. Needless to say, I am a bit despondent about this but there is nothing I can do but wait till tomorrow. I just hope they can find the right pads. I looked at every 2001 Dodge truck pad they had on the Napa site, none of them show the spring arm like these pads have. I checked other years too. Funny thing is the part number on the box matches the part number on the web site which matches the part number on the receipt. Ugh.

OK, my rant is now over. Not Napa-bashing here, but I really wish this had not happened. I had other plans for tomorrow. I also hope they will take back the incorrect pads even though there is red anti-squeal compound on them. Soon as I saw I had the wrong pads I tried to clean it off, but there is still some there.

 

[mechtech2]

Don't let the antisqueal sauce dry before installation!
You put this on last, and assemble them with everything else being prepped.
Then pump up the brake pedal ans do the other side.
You want them to seat metal on metal, with no ambiguous and shifting semi hard sauce in between.
The sauce dampens [mostly] high frequency vibrations - it simply sucks them up. It is NOT wanted on the actual contact area of pad to caliper or piston.

 

[labman]

I always put the sauce on before I jacked up the car and never had a problem. The job before last, I asked for the sauce at Oreily's and they offered me a little packet of silicone grease. Well I have a whole tube of Sil-Glyde. Use it, and on the next job too. That was over a year ago, and just like when I let the sauce dry, no squeal.

Funny thing, I have had so much trouble with stuff from Oreily's being wrong, I am going to NAPA now.

 

[andyd]

despite having something extra, would the pads work?

 

[Jimmy9190]

Well now another couple of problems happened today. The Napa that was supposed to be open today, well it was closed. The nearest one that was open was about an 80 mile round trip. So I got a set of pads at AAP just up the street. I came home, went to start on the driver's side again and I see that the new rotor has chips, severe cracks and broken pieces at 3 different places slong the vanes in between the rotor surfaces. Almost as if it had been dropped or had been damaged in shipping somehow. I am not about to put that rotor on so I went back to AAP and got a set of Wearever rotors, strangely enough the rotor, box and the label on the side of the box all look identical to the Napa label on the Napa rotor box. The Wearever box even has cross reference numbers for Bendix, Napa and some other manufacturer right on their label. Obviously the same factory in China produces all the rotors at least for Napa and AAP. Makes me wonder where my parts really come from. Very few things are US made anymore I guess. Someone somewhere is making lots of money with all the outsourcing to China. I just hope Napa gives me a 100% refund on their parts tomorrow.

Then I finished the job and went to test drive and bed the pads. I got a mile or so down the road and someone is beeping their horn at me at the stop light. I had the window down and thought I saw smoke, pulled over right away and the driver's side wheel is very hot and there is smoke coming from the back side of it. So I got home as easily as I could and pulled the wheel, found nothing out of the ordinary. I siphoned off about a tablespoon of brake fluid from the master cylinder and C-clamped that side caliper back in on the piston again. Drove it back to AAP, wheel wasn't smoking anymore and was just warm to the touch. I discussed it with the guys there, they think it must have been some of the caliper grease or anti-squeal compound got on the pad surface and caused the smoke. But the front wheels are still hot to the touch and smell hot after driving to bed the pads and driving a bit around town tonight. I am thinking it's just friction from having new thicker pads and rotors and it should let up soon. Truck brakes in a perfect straight line, doesn't pull at all when braking and the shudder/vibration from warped rotors is completely gone. But I have never seen wheels be hot like that after only replacing pads and rotors.

Any ideas on that are greatly appreciated. This has been a brake job from the place the censors won't let me type...What a pain.