Is brake "warpage" damaging?....

Joined
Apr 13, 2013
Messages
8,006
Location
FL, USA
A little over a year ago I had the front brakes replaced on my Accord (new pads and rotors). Well about 5 months into the new brakes they started to vibrate when braking, now they are back to how bad they were a year ago...making the steering wheel wobble slightly (not crazy or anything) and making the car "pulsate" if you will, when coming to a stop. It really makes the whole driving experience less enjoyable. I do want to have them replaced, but dont have the money right now. Is this damaging to any other components? In other words, should I replace sooner than later? Pads should have plenty of life left, and rotors are only a year old! I have to wonder if the short trips have a role in this (leaving deposits from pads, but no long stops to "clean" them off).
 
Joined
Jan 27, 2011
Messages
3,061
Location
usa
No, you're not damaging anything else, except perhaps another car and/or your own bumper and grille, if you don't stop in time :devil: It's not damaging; it's damaged already! Replace the pads and rotors as soon as you can. Be sure to use quality name-brand pads and rotors. Good rotors include Centric Premium and Fremax. Good pads include Akebono, Wagner Thermoquiet, Advics, ATE, EBC, Hawk, and a few others. Avoid the Chinese Bendix CT3 because they're Chinese now. Most rotors are Chinese, too, but they are not as avoidable as pads. The Fremax rotors are made in Brazil. I'd recommend the Akebono ProACT pads and Fremax rotors because there is no bedding-in required or any special break-in process.
 
Joined
Jun 2, 2009
Messages
2,104
Location
Wisconsin
The rotors are warping. Always replace rotors and pads in pairs. When you replace the rotors this next time make sure you clean the hub really well. Also do a run-out test to find the best configuration for your rotors (unless your rotors have a screw that secures them to the hub, then they can only go on one way). Cleaning the hub and getting quality rotors that have very little run-out to begin with is very important. The highest grade Raybestos are good ones.
 

gregk24

Thread starter
Joined
Apr 13, 2013
Messages
8,006
Location
FL, USA
Originally Posted By: tommygunn
No, you're not damaging anything else, except perhaps another car and/or your own bumper and grille, if you don't stop in time :devil: It's not damaging; it's damaged already! Replace the pads and rotors as soon as you can. Be sure to use quality name-brand pads and rotors. Good rotors include Centric Premium and Fremax. Good pads include Akebono, Wagner Thermoquiet, Advics, ATE, EBC, Hawk, and a few others. Avoid the Chinese Bendix CT3 because they're Chinese now. Most rotors are Chinese, too, but they are not as avoidable as pads. The Fremax rotors are made in Brazil. I'd recommend the Akebono ProACT pads and Fremax rotors because there is no bedding-in required or any special break-in process.
I have done a couple highway speed stops, but they just wobble the whole time and the end result is the next day when driving around town they still wobble. My question is, does all that vibrating hurt other parts of the car...steering, suspension, other brake parts etc. I will see if I can purchase some better quality parts and getting my local shop to install them. They use Napa parts so I thought they would be good.
 
Joined
Jun 28, 2012
Messages
2,998
Location
Southern Illinois
Buy the best rotors and the medium hard pads. Make sure your not trapping brake pressure somewhere, bad hoses, bad check valve or bad master cylinder.
 
Joined
Sep 23, 2014
Messages
1,823
Location
Toronto Canada
When the car is being shaken by the action of warped rotors [probably not warped but deposits] every suspension and steering component is wearing much fast than usual. If you leave it in this condition, it will lead to other problems down the road. Most likely it is just deposits, not warped rotors. I would try to clean them up with hard braking before spending any money. http://www.stoptech.com/technical-support/technical-white-papers
 
Joined
Aug 30, 2004
Messages
25,169
Location
CA
The parts were probably fine to begin with, but they were not installed properly. I am willing to bet that lateral runout was not checked, and the hub flange was not properly cleaned.
 
Joined
Apr 3, 2013
Messages
792
Location
Denmark
I recently mounted some ferodo premium pads and coated discs on the family Mazda 6. So far they have bin exelent with low dust(even during brake in) good bite and no noise. and important for many of you nice people here. They are made in the US. But as mentioned here.. it sounds like the hubs has not bin cleaned from rust or perhaps the lugnuts/bolts where tightened wrong/unevenly.
 
Last edited:
Joined
Feb 12, 2013
Messages
3,117
Location
Virginia
Greg does a lot of stop & go driving. New rotors installed just before a hot Fla summer - lots of braking - I'm guessing they went through thermal shock and warped. Since the rotors are relatively new, I'd have them turned so they are straight again. It might be cheaper to buy a new set of rotors. Either way - break them in gently. Avoid harsh hard stops when possible and spirited driving requiring heavy braking. Brake early and gently for at least 500 miles. This beds in the rotors with a natural heat treat that resists high thermal loading in the future. The process of getting them a little hot, and then cool, will heat treat them. Most new car owners manuals tell you to drive gently for the 1st 500-1000 miles - this is one of the reasons.
 
Joined
Feb 16, 2010
Messages
426
Location
Detroit
Originally Posted By: gregk24
A little over a year ago I had the front brakes replaced on my Accord (new pads and rotors). Well about 5 months into the new brakes they started to vibrate when braking, now they are back to how bad they were a year ago...making the steering wheel wobble slightly (not crazy or anything) and making the car "pulsate" if you will, when coming to a stop. It really makes the whole driving experience less enjoyable. I do want to have them replaced, but dont have the money right now. Is this damaging to any other components? In other words, should I replace sooner than later? Pads should have plenty of life left, and rotors are only a year old! I have to wonder if the short trips have a role in this (leaving deposits from pads, but no long stops to "clean" them off).
Brake pedal pulsation is caused by having initial rotor runout exceeding .002. Honda requires an on car brake lathes to be used to get to that number, most brake shops do not have one. Other causes are improper wheel torque (impact wrench use) Dirty slides not allowing the brake pad to retract properly. I would take it back to the installing shop as long as you havent had the wheels off they should warranty it. Here is the Honda procedure 00-088 January 24, 2014 Applies To: ALL Models On-Car Brake Disc Refinishing Equipment and Guidelines (Supersedes 00-088 Brake Disc Refinishing Using Kwik-Way and Accu-Turn Lathes, dated November 5, 2013, to revise the information marked with the black bars and asterisks) REVISION SUMMARY The Pro-Cut lathe was added to the INTRODUCTION and a new section was created for Pro-Cut lathes. INTRODUCTION American Honda does not allow replacement of brake discs under warranty unless the brake disc is beyond its service limit for refinishing. If the brake disc is within its service limit, you must refinish it. Maximum refinishing limits may be found in the Conventional Brakes section of the appropriate electronic service manual. Refinish brake discs only when they are scored or out of specification for runout or parallelism. See the appropriate electronic service manual for the specifications. American Honda requires refinishing of the front brake discs with an on-car brake lathe that mounts to the steering knuckle or hub using specially designed Honda/Acura specific adapters. It is critical to use an on-car steering knuckle-mounted lathe because it corrects the hub and disc runout as an assembly. Even a very small amount of runout, which may not be felt initially, will grow and will be felt as brake pulsation as the discs are subjected to heat and wear over time and mileage. *You must use one of the following lathes to refinish a brake disc under warranty: ^ Pro-Cut: T/N PCIPFM92HON ^ Kwik-Way: T/N KWY-108000501 ^ Accu-Turn: T/N ACCHONOCLPKG* NOTE : The Kwik-Way and Accu-Turn lathes and their related parts and adapters have been discontinued from the tool manufacturers and are no longer available for purchase through the Honda Tool and Equipment Program. Any KWY part number listed within this bulletin are for identification purposes only. A power driver is required for the S2000 and is highly recommended for all other models. The Kwik-Way power driver model number is KWY-108000110. Here are some advantages of using power drivers: ^ The disc is rotated at the optimum speed for a smooth and consistent cut. ^ There is no need to climb in and out of the vehicle to start and stop the engine or to shift the transmission. ^ Securing the opposite wheel with a tie-down strap is not required. ^ There is no waiting for the engine to return to idle and no concern about engine speed changes that can adversely affect brake disc cut and finish. ^ The Traction Control System (TCS) is not involved. ^ Consistent cutting speed increases cutting tool life. ORDERING INFORMATION The Pro-Cut lathe and Honda/Acura adapters are available through the Honda Tool and Equipment Program. To order, go to the Honda Tool and Equipment program catalog on the iN (select Service > Service Bay > Tool and Equipment Program > Online Catalog), or call. Phone lines are open Monday through Friday from 7:30 a.m. to 7:00 p.m. Central Time. WARRANTY CLAIM INFORMATION None, this bulletin is for information only. *PRO-CUT LATHE Make sure you are using the correct adapter and refinish the brake disc. ^ 4 Lug Honda/Acura Adapter, Red Label (56 mm/4 x 100 mm): T/N PC150996 ^ 5 Lug Honda/Acura Adapter, Blue Label (64 mm/5 x 114.3 mm and 120 mm): T/N PC150997 ^ 4 and 5 Lug Honda/Acura Adapter, Yellow Label (70 mm/5 x 114.3 and 4 x 114.3 mm): T/N PC150998 For more information about how to refinish the brake disc, which includes information about setting up the vehicle, setting up the lathe, and cutting the discs, refer to the Pro-Cut Lathe Technical Manual, or call Pro-Cut to schedule training. NOTE : You must use the listed Pro-Cut hub adapters to meet Honda's required specifications for run-out on warranty repairs. Do not use Pro-Cut's universal hub adapters, because they do not meet Honda's run-out specifications. Pro-Cut Honda Adapters are available through the Honda Tool and Equipment Program on the Interactive Network (iN). Click on Service, Service Bay, Tool and Equipment Program. Click on Alignment, Wheel, and Brake Equipment, and then click On-Car Brake Lathes and Accessories.* KWIK-WAY AND ACCU-TURN LATHE Use the following guidelines that show the Kwik-Way lathe setup; the Accu-Turn brake lathe setup is similar. NOTE : You can use an on-car lathe to refinish the rear discs on some models if the rear caliper mounts are low enough to allow the lathe to clear the vehicle body. Refer to REAR BRAKE DISC for more information. Setting Up the Vehicle Put the transmission in Neutral. If you are not using the power drive system, start the engine, and let it warm up to its normal operating temperature so the idle speed will stabilize to its lowest rpm. NOTE : AWD vehicles must have all four wheels off of the shop floor. Raise the vehicle on a lift. Check for loose wheel bearings. You must replace loose wheel bearings before you refinish the brake discs. If you do not, the brake lathe will not correct for brake disc runout, resulting in an uneven finish and brake pulsation. Remove the front wheels, then reinstall the wheel nuts with flat washers to compensate for the removed wheel. Torque the wheel nuts to the required specification (see the appropriate electronic service manual). Remove the caliper assembly. Use a wire or an S-hook to hold the caliper to the spring or damper tower. Do not kink the brake hose or use it to support the caliper. If you are not using the power drive system and the vehicle has TCS or VSA, make sure you install a brake pad spreader between the pads on the hanging caliper. Also, make sure the TCS or VSA is turned off anytime the engine is started. If the system is not turned off, the brakes could activate, causing the brake pads on the hanging caliper to hit each other or the caliper pistons to fall out. Install the vibration damper on the brake disc. If you are not using the power drive system, make sure you install the protective band around the wheel nuts. If you are not using the power drive system, use a fabric tie-down strap to secure the brake disc that is opposite to the one you are refinishing. If you are working on a Prelude with ATTS, do not use a tie-down strap; let both wheels turn freely. Mounting the Brake Lathe Remove the tool bed from the brake lathe, then mount the brake lathe to the steering knuckle with a Honda 1-piece speed mount. These mounts provide quicker, more accurate mounting. Honda 1-Piece Speed Mounts ^ P/N KWY-108006000 (for most models) ^ P/N KWY-108007500 (Odyssey, Pilot, and Ridgeline with two-piston calipers) ^ P/N KWY-108007600 (2009 and newer Pilot) Attaching the Power Drive System 1. Make sure the drive motor assembly on the power drive system is level with the brake disc. 2. Attach the mounting yoke to the brake disc, and secure it with one of the wheel nuts. Torque the wheel nut to the required specification (see the appropriate electronic service manual). NOTE :Yoke and driveshaft assemblies may vary on the power drive system. 3. Attach the driveshaft on the drive motor assembly to the mounting yoke, making sure the center line of the driveshaft is level with the spindle nut on the wheel hub. 4. Set the lower toggle switch on the drive motor assembly to FWD (counterclockwise rotation) or REV (clockwise rotation). Setting Up and Adjusting the Brake Lathe Use Kwik-Way cutting bits, P/N KWY-109109223, and the holding screws that come with them. These bits are stamped KW. Before you use the brake lathe, inspect the tips of the cutting bits with a magnifying glass to make sure the tips are not worn out. Each bit has three tips. If a tip is worn, rotate the bit, and use a new tip. A worn tip produces a poor finish and may cause chattering. Reinstall the tool bed on the brake lathe with the top of the cutting bits facing up and the feed knobs facing down. Adjust the tool bed until the brake disc is centered between the cutting bits. For proper refinishing, the brake disc must turn toward the top of the cutting bits. Do not set the cutting depth on the brake lathe to more than 0.2 mm (0.008 in.). This is two divisions on the cutting knob. Make sure you start your cut at least 3 mm (0.12 in.) beyond the worn area on the brake disc. If you are cutting larger diameter brake discs, make sure you use the 150 cutting bit holders. Each bit holder is clearly marked for proper installation on the tool holder. Cutting the Brake Disc To get the smoothest cut and the best brake disc finish, always use the slowest feed speed on the tool bed feed motor. Place the drive belt on the smallest pulley of the feed motor and on the largest pulley of the hand wheel. Make sure the lower toggle switch on the power drive system drive motor assembly is set to the proper rotation to turn the brake disc toward the top of the cutting bits. Plug the tool bed feed motor into the power outlet on the drive motor assembly, then turn on the drive motor with the upper toggle switch on the assembly. If you are not using the power drive system, make sure the transmission is in 1st gear (2nd gear on Preludes with ATTS) or Reverse and the engine is idling, but not at a fast idle. If the transmission and engine are at higher gears and speeds, you will damage the cutting bits. Turn on the tool bed feed motor, and snap it into place; there should be tension on the feed belt. Cut the brake disc until the cutting bits clear the outer edge of the disc. The cutting bits should produce a smooth, consistent finish with no chatter marks or grooves. If the disc did not clean up entirely on the first pass, reset the brake lathe and make a second pass. Finishing the Job Remove the vibration damper and the protective band (if used). Use a micrometer to measure the thickness of the brake disc. Make sure the thickness is within the service manual specifications. Clean the brake disc with soapy water or brake cleaner, then wipe it dry. Use a vacuum cleaner to remove any dust or chips, but do not use compressed air. Unplug the tool bed feed motor from the drive motor assembly, and remove the mounting yoke from the brake disc. Remove the speed mount from the steering knuckle. Apply a small amount of Molykote 77 grease to the brake pad shims. Reinstall the caliper assembly. (If you did not use the power drive system, use the brake pad spreader to push the pistons back into the caliper.) Torque the nuts and bolts to the required specification (see the appropriate electronic service manual). Refinish the other front brake disc using the same guidelines. Check the brake fluid level, then test-drive the vehicle to make sure the brake pedal is firm and does not pulsate. Lightly apply the brakes about 20 times during the test-drive to seat the brake pads. REAR BRAKE DISCS It is possible to use an on-car lathe on some models if the rear caliper mounts are low enough to clear the vehicle body. A power driver is needed for front drive models. Refinish rear brake discs on bench-mounted equipment if necessary. Follow the same guidelines you used for refinishing front brake discs, noting these differences: ^ For VTM-4: If you are not using the power drive system, make sure the transmission is in low gear and the VTM-4 LOCK switch is on (the light in the switch is lit). ^ Mount the brake lathe to the rear knuckle with the Honda 2-Piece Adapter. Honda 2-Piece Adapter ^ P/N KWY-108102504 ^ P/N KWY-108102534 (2008 and newer models) Disclaimer © 2014 ALLDATA LLC. All rights reserved. Terms and Condition
 
Joined
Dec 2, 2002
Messages
6,388
Location
Washington St.
Almost everyone is saying the rotors are warped, and no one has measured the runout. They probably are not warped. They probably have uneven deposits of friction material on the rotors. Yes, this brake judder is wearing all the parts that get shaken. http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths Greg, can you or a helper do some brake work on your car? I'd take the rotors off, sandpaper the surfaces, wash with brakeclean, be sure the mounting surface is clean, put them back on. Buy new pads rated for higher temperature. If the new pads have a break in procedure, follow that. Fresh brake fluid is important periodically, but not for this problem.
 
Joined
Aug 21, 2013
Messages
4,276
Location
Central Maryland
Originally Posted By: Ken2
Almost everyone is saying the rotors are warped, and no one has measured the runout.
I have measured run-out, and often I have found it. On my recent vehicles it came from poorly manufactured rotors, not the hubs. On a previous vehicle it came from running a couple months with 600+ ft.lb tightened lug nuts. I had to replace some of the lugs, the threads were so buttressed.
Originally Posted By: Ken2
They probably are not warped.
Maybe, maybe not.
Originally Posted By: Ken2
They probably have uneven deposits of friction material on the rotors. Yes, this brake judder is wearing all the parts that get shaken. http://www.stoptech.com/technical-support/technical-white-papers/-warped-brake-disc-and-other-myths
Yes, I encourage everyone to read this paper CAREFULLY and then stop arguing "warped" and "not warped" until measuring run-out. But assuming a rotor is not warped in this age of cheap imported rotors is just as bad an assumption as thinking it warped from hard usage or bad metallurgy after installation. From the paper: "With one qualifier, presuming that the hub and wheel flange are flat and in good condition and that the wheel bolts or hat mounting hardware is in good condition, installed correctly and tightened uniformly and in the correct order to the recommended torque specification..." That's the expert speaking. He's saying over-torquing or non-uniform torquing of lug nuts causes problems. "Installed correctly" means checked for runout and corrected as necessary. Mounting on top of poor machining, hub or rotor casting flash, or dirt causes an eccentric condition as well. We may not like to call it "warp" but all of these mistakes cause the rotor wobble that leads to uneven friction material buildup and pedal pulsation, even if the rotor was flat when new and unmounted. The uneven deposits of friction material come from misuse/poor break-in, but also from eccentrically cut or mounted rotors. The pulsation feeling occurs weeks or months after a brake job, and so people think that the rotors warped after installation. In fact they may have always been warped/eccentric, or got twisted up the moment the wheels were put on after the brake job, but until the brake pad material builds up, you can't feel it. So the point of the article is hard usage or bad metallurgy is not going to warp a good rotor. But the problems have to come from somewhere, so the pulsating rotors need to be remounted and cleaned of friction material, turned or replaced. But someone on the forums always has to come along as say "it's not warped", no it's not so simple to make that call. It may not have warped before the brake job, but it may have been mounted eccentric or been overtorqued or even been manufactured warped/eccentric, it just feels good under the compensating floating caliper until the friction material builds up.
 
Top