Brake rotors play an important part in the braking system. It is common for oem rotors to have the minimum thickness stamped on the rotor hub as is the case with the ceramic pccb brake option. The minimum thickness should be cast right into the area around the rotor. One of the most difficult specs to understand is brake rotor thicknesses. Jack up the front of the vehicle and support it with safety stands. It is the friction between brake pads and rotors that cause your car to slow down and stop. What are the minimum thickness specs for a front brake. Use a micrometer and measure the brake rotor thickness 0. Rotor thickness and drum diameter if a rotor is close to or at the minimum thickness specification which is stamped on the rotor or may be found in a brake service reference book, it is too thin to be resurfaced and must be replaced. Disc brake rotor minimum thickness also known as scrap thickness is the minimum safe working thickness of a rotor at which it must be replaced. If rotor is not within specifications, replace it with a premium wagner eshield rotor. Where can you find the minimum thickness for rotors answers. Service information the minimum thickness cast into a rotor is the thickness at which the rotor should be discarded and is no longer suitable for service.
The book says they should be either stamped or cast into the hub area. Porsche boxster brake rotor replacement 986 987 199708. The correct way to determine your rotor thickness is to measure the rotor between the brake pad surfaces see picture below. Compare the smallest value measured to the minimum thickness specifications stamped on the brake rotor. The rear rotors are solid, and the brake caliper handles parking brake features. The maximum life of a disc rotor is achieved when it reaches what we call the minimum thickness. Front disc brakes all 19941999 2500 and 19941997 3500 available w optional abs 19981999 3500. If you cant find this information, use the following chart to determine if your rotors need to be replaced. As the rotor reaches its minimum thickness, the braking distance increases, sometimes up to 4 meters. Any significant grooving means the rotor has to be remachined if there is enough materialthickness left or be replaced. This level can be found engraved on the sides of the rotor, within the veins of the rotor, or on the hat of the rotor. I agree, if the rotors have,000 miles, then they are toast but replacing rotors with each pad change may be excessive. Most new cars 1999 and above come with rotors at each wheel. Brake pads should be replaced when there is 18 to 316 of friction material left on the steel backing plate.
If the rotor is below the minimum thickness, the rotor must be replaced. A technician must remove the wheel and use a micrometer on the rotor to measure its thickness accurately. Premium wheelend brake products bendix esd225 air disc. Before you buy brake pads, youll want to read this.
Use a micrometer at the thinnest point on the surface of the rotor where it meets the pads to measure the minimum operational thickness. This thickness is not usually used on a daily basis but is listed in most specification books. Types disc brake rotor 1amvr10374 tl 20082007 rear. You can inspect the brake pads by lifting your car on a jack and removing the tire. When you press the brake pedal, the calipers cause the brake pads to clamp down on the rotors also called brake discs to slow the spinning wheels. Today my wife took her car in for a state inspection. If my pad thickness, rotor thickness, and rotor runout are within spec, what else could cause the shakingpulsating symptom during braking on a downhill. Disc brake rotor minimum thickness rmt is the minimum safe working thickness of a rotor. Continued operation at or below rotor minimum thickness can lead to brake system failure. Mini cooper r56 brake pad and rotor specification checking. In as little as fifteen minutes, a brake specialist can give your cars braking system a safety check. Brake rotor information for your infiniti vehicle nissan. The only real numbers they give are that you should measure and record rotor thickness in 612 different points on the contact surface and you should not see more than 0.
Nominal thickness is the thickness of the rotor when it is new. The minimum thickness cast into the rotor supersedes all published information. Disc rotor minimum thickness performance brake disc. The specifications for the particular car will show the minimum thickness that a rotor can still be used. Most late model vehicles feature fourwheel disc brakes and brake rotors. How do you measure thickness of brake rotors answers. Sep 21, 2018 to accurately measure against the minimum thickness use a micrometer at the thinnest point on the surface of the rotor where it meets the pads. Oct 27, 2002 the metallurgical changes in the rotor often cause the hard spots to return after a few thousand miles so replacing the rotor may be the best longterm fix. To withstand the mechanical and thermal stresses of braking, brake rotors are required to be replaced if they are worn thinner than a certain minimum thickness. When machining a rotor, the thickness of one friction disc to the other should be taken into consideration. A brake rotor is a smooth metal disc attached to the wheel hub. This is the thinnest a rotor can be machined to and still be put back into service.
This blackcolored coating prevents corrosion, makes removal for service fast and simple, and is visually attractive for open spoke wheels. Mechanical parts and labor electronic estimating cd. This heat energy is created by the driver when he or she presses the brake pedal. Where i live we have no safety inspections, but if there are where you live there may be a state regulation that prohibits issuing a safety certificate if a car is found to have undersized rotors. If the rotor is below the minimum thickness, the rotor. Andrew markel visits minimum wear specification on brake rotors and how the specification is related to brake pad wear and how far the caliper has to push the pads. Rotors should be replaced by 70k miles on most vehicles, depending. Rotate the brake rotor and note the amount of runout by reading the dial indicator. To accurately measure against the minimum thickness use. I need to find a brake rotor specification discard. For example, if a rotor is gouged on one friction surface due to metal to metal contact with the brake pad but not the other, it could be possible to machine the gouge out and the rotor still be over machine to thickness. Brake rotor thickness requirements vary by vehicle make, model and year, but the minimum allowable thickness is always cast on an unmachined surface, or alternate part, of the rotor. Porsche boxster brake rotor replacement 986 987 1997. We marked the min thickness on the surface,it means you should replace the brake disc rotor when the thickness with minimum thickness to ensure save ridding.
Measure the thickness of the rotor 25mm in front of the outer edge using a vernier caliper. Dec 26, 2018 knowing the minimum rotor thickness specification of your vehicle is very important as if the rotor thickness of your car is thinner than the minimum level, your safety will be put in danger. A technician must remove the wheel and use a micrometer on the rotor to. Knowing the minimum rotor thickness specification of your vehicle is very important as if the rotor thickness of your car is thinner than the minimum level, your safety will be put in danger. Min thickness front vented steel rotor boxster 19972004.
As the rotor reaches its minimum thickness, braking distance increases. Engraved on the side of your rotor you can find the minimum operational thickness. Older cars may have drums instead of rotors at the rear wheels. On most models, you do not need to remove the caliper or unscrew the brake pad mounting pin in order to inspect the thickness of the brake pad. Continued operation at or below minimum thickness can lead to brake system failure. After this happens for a while and the brakes are applied you feel a pedal pulsation as the pads follow the rotor thickness variation. This measurement should be taken at a minimum of 10 points around the circumference. A precisioncut finish of the outer diameter of the rotor prevents improper balance issues that may result in vehicle control loss. When new, brake pads are nearly 12inch thick, depending on the model of your toyota. If any portion of the rotor is thinner than the minimum thickness it must be discarded. To measure the brake rotor thickness and parallelism proceed as follows. A wornout or thinner rotor has less mass than a normal one, leading to the decrease in its ability to absorb and dissipate heat. I know the bolt pattern is the same as well as the front and back rotor sizes diameter and thickness. Rotor thickness and drum diameter if a rotor is close to or at the minimum thickness specification which is stamped on the rotor or may be found in a brake service reference book, it.
It should turn smoothly with no interruptions or sticking. Lost jeeps view topic minimum front rotor thickness. Any significant grooving means the rotor has to be remachined if there is enough material thickness left or be replaced. The thickness of brake rotors are measured with a tool called a caliper. A technician measures the brake rotor thickness with a micrometer in either thousandths of an inch or hundredths of a millimeter. Dec 18, 2009 can anyone tell me what the minimum allowable brake pad and rotor thickness before a pad andor rotor change is needed. The minimum brake rotor thickness for the front and back rotors on a 1992 honda accord is 21mm. Inspect rotor for lateral runout, parallelism and minimum thickness specification. They should measure 1 or less for the 1 ld brakes and 1. What this means is that every time a portion of the rotor comes around the rotor makes some contact with the pads and wears the rotor thickness away at that point. What are the minimum brake rotor thickness specs for a 2005 subaru outback.
While i was at it, i also measured the pad and rotor thickness. Tight tolerance specifications reduce thickness variation and lateral runout, ensure a balanced rotor, and reduce pedal pulsation, brake noise while extending pad life. The minimun thickness is stamped on the inside of the rotor. The purpose of having a machine to thickness is to provide enough rotor material. Measure your rotors before and after machining to be sure they meet the required minimum thickness specification. Figure a11 disc wear measurement piper aztec pressure plate back plate 0. The rotor s minimum thickness tells you the minimum operational level of your rotor. The brake shoes are not fixed on the support plate, which allows. The dealer told her that all 4 rotors and all brake pads need to be re read more. If rotor thickness is within specification, use an approved oncar brake lathe and machine the brake rotor.
This micrometer is used for precisely measuring thickness of brake rotor surfaces. If the rotor is too thin, it will not dissipate heat correctly and be more prone to warping. Disc brake service wagner brake brake pads, brake rotors. Makemodel year application qualifier product part number a3acura 20112009 base. Jul 04, 2016 rotor thickness is a manufacturer spec, no government input exists as to the thickness of a rotor. The basics of rotor runout phoenix systems brake bleeder. Continued use of disc rotors below rmt can lead to brake system. Brake rotor thicknessrunout jim, if you find out,please let me know, too. What are the minimum thickness specs for a front brake rotor. Rotor minimum thickness is determined by the motor vehicle manufacturer during the initial vehicle design also refer to australian standard 3617. Disc rotor minimum thickness performance brake disc rotors and.
Rotors which are below this thickness will not offer adequate or reliable braking. This minimum thickness is stamped on the edge of the rotor. Rotor thickness is a manufacturer spec, no government input exists as to the thickness of a rotor. Mazda 3 service manual rear brake disc inspection disc. Chrysler brake rotor and pad minimum specifications. The m10 bolts that fasten the rotor to the hub on the standard 02 are 10. Rotors play an important role in your braking system. Sep 22, 2015 when machining a rotor, the thickness of one friction disc to the other should be taken into consideration. If your rotor needs to be cut or has worn passed this thickness, youll need new rotors.
Disc rotor minimum thickness performance brake disc rotors. This thickness is not usually used on a daily basis, but is listed in most specification books. Can anyone tell me what the minimum allowable brake pad and rotor thickness before a pad andor rotor change is needed. Description specification disc brake rotor ventilated front max. As long as you are above the minimum thickness and the rotor is straight, and without surface defects using the rotor is not dangerous. To accurately measure against the minimum thickness use a micrometer at the thinnest point on the surface of the rotor where it meets the pads. Plain brake rotors may be turned on a brake lathe to remove scoring and to true the disc surfaces until this minimum brake tech information brakes 101. Andrew markel visits minimum wear specification on brake rotors and how the specification is related to brake pad wear and how far the caliper.