Lateral Run-Out Correction Plates

an important step in completing a brake service is to check for disc rotor lateral run-out lateral run-out is the primary cause of brake pedal pulsation and brake comebacks since it leads to disk thickness variations or uneven wearing of the rotor this video will demonstrate how to measure the rotor lateral run out and if out of specification how to correct it when installing a new or resurfaced rotor care must be taken to ensure that the combined rotor and hub assembly meet the manufacturers specification for allowable lateral run-out which in many cases is less than two thousands of an inch or 0.1 millimeters to measure for lateral run-out takes about 60 seconds and all that is needed is a dial indicator and a set of conical washers to ensure accurate measurements we highly recommend that you thoroughly clean both of the mating surfaces of the hub and the rotor a hub cleaning tool makes it easy to clean around each wheel stud make sure all areas are free from rust and debris in this demonstration we will be installing a high quality new rotor at meet specifications but due to the stack tolerances of the hub and rotor the total run-out may still be greater than the allowed specifications install a machine or new rotor onto the hub using the vehicle's lug nuts and torque to the manufacturer's specifications we highly recommend the use of conical washers to insure the loader properly seats on to the hub attach a dial indicator to a rigid part of the vehicle spindle tighten the dial indicator arm in a position where the needle of the gauge contacts the rotor approximately a half inch from its outermost diameter lift the spring-loaded needle on the gauge up off of the rotor a few times to ensure that the needle is making good contact on the rotor friction surface notice how the gauge oscillates back and forth between the high and low points on the rotor the lowest reading is the lowest point on the rotor after determining the low spot rotate the face of the gauge to set zero at this needle location rotate the rotor again to ensure the low spot is exactly at the zero setting continue rotating the rotor to determine the high spot this is the location of the highest lateral run-out record this amount as this vehicle is well in excess of mm or 0.1 millimeters specification set by the vehicle manufacturer first try to index the rotor by rotating it on the hub 180 degrees if this does not correct the problem use a break align lateral run-out correction plate run-out greater than six thousandths or 0.15 millimeters means there may be a more serious problem you will need to determine whether the hub or the rotor is the cause and replace or repair accordingly the dial indicator shows six thousandths or 0.15 millimeters of lateral run-out mark the rotor in the exact location of this high spot rotate the rotor again and stop the rotation when you reach the highest reading where the needle contacts the rotor is the exact location of the high spot mark this location on both the rotor and the closest wheel stud marking both points is very important pivot the dial indicator out of the way it is helpful to rotate the rotor to bring the high spot to top dead center or at 12 o'clock using the brake align application chart locate the year and model of the vehicle being serviced this 2010 chevrolet impala will use a BA eight zero one zero six correction plate the zero six in the part number indicates the amount of taper or correction the hub correction plates are available in two increments three thousandths or 0.075 millimeters and six thousandths or 0.15 millimeters since we have 0.15 millimeters or six thousandths of run-out we will select a VA eight zero one zero six once the correction plate has been selected remove the rotor note the wheel stud that was previously marked on the location of the high spot on this application there are 10 holes on the plate that will allow for proper alignment of the plate even in instances when the high spot is in between two wheel studs as it does in this case the hub correction plate has a v-notch on the inside diameter install the correction plate onto the hub being careful to align the v-notch of the plate so that it falls between two studs nearest to the March wheel stud indicating the high spot reinstall the rotor on to its original position on the hub lining of the markings on the rotor with the Mart wheel stud using the conical washers install and hand tighten all of the lug nuts next torque all lug nuts to the manufacturers specification pivot the dial indicator back into position onto the rotor turn the rotor clockwise to double check for any lateral run-out the total amount of run-out is now well within the manufacturer's specifications the key point to remember in this situation is that the new rotor we installed was within the manufacturers specs the problem was with the hub assembly we were able to fix the problem easily and cost-effectively with a brake align lateral run-out correction plate versus the major expense of replacing the entire hub assembly please note have we not replaced the rotor and not corrected for the lateral run-out the test drive would have been satisfactory the pulsation would have returned in as little as three thousand miles or five thousand kilometers so the next time you're doing a brake job to prevent pedal pulsation and brake comebacks be sure and measure for lateral run-out with a proper tools

Channel: Raybestos Brand

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Keywords: RAYCheck4LateralRunout

Id: 2kIhrGviecc

Length: 6min 9sec (369 seconds)

Published: Tue Feb 05 2013