Travis, Runout can be measured off the vehicle, however to get an accurate reading, runout needs to be measured after the rotor is mounted on the vehicle. The reason for this is stacked tolerances. Stacked tolerances use the combined runout of all components(rotor, hub, bearing). Most OEM's recommend correcting excessive runout with shims or an on the car lathe.
I know this video is old, but I found this useful as I'm going to be checking my bearings and rotors. I've been having bad vibration after replacing brakes and rotors multiple times. The car vibrates over 50 mph and it shakes bad when hitting the brakes from highway speeds. Don't really feel alot in the brake pedal. Would you have any clue what this could be? I've got new tires just a few months ago and an alignment. Had tires rebalanced and rotated multiple times. Steering also feels sloppy. Wonder if there's a bad tie rod. I don't have any play in either front wheel though. 2017 Nissan Altima
Turning the rotor properly cuts the rotor runout to zero. Remounting the rotor allows a remeasure, however, because of stacking variation, (other components mounting the rotor) the total runout may not be zero. Look at other videos for how that is dealt with (shims etc). Good Luck!!
I know that it is mentioned as a possibility, but I personally never worry about it, I swap my pads long before turning the rotor is necessary, Classic? 79 pickup; 78 motorcycle, probably not what would be considered classic but they're mine and what I work on.
When you have rotors turned they will have 0 run out. What you would want to do is to check the run out at the hub, just outside of the lugs. If you have no run out then you are good to go. Mount the rotor and it will have no pulsation. If it has more than .001 of run out, then you will have pulsation with the newly turned rotor, if not immediately then after some miles when the rotor bends with the distorted hub. You will need to either use brake align rotor shims to offset the hub run out or get a new hub.
Travis, Runout can be measured off the vehicle, however to get an accurate reading, runout needs to be measured after the rotor is mounted on the vehicle. The reason for this is stacked tolerances. Stacked tolerances use the combined runout of all components(rotor, hub, bearing). Most OEM's recommend correcting excessive runout with shims or an on the car lathe.
Best video on UA-cam on this topic.
Fantastic video on this topic! Direct, clear and concise! A+++
I know this video is old, but I found this useful as I'm going to be checking my bearings and rotors. I've been having bad vibration after replacing brakes and rotors multiple times. The car vibrates over 50 mph and it shakes bad when hitting the brakes from highway speeds. Don't really feel alot in the brake pedal. Would you have any clue what this could be? I've got new tires just a few months ago and an alignment. Had tires rebalanced and rotated multiple times. Steering also feels sloppy. Wonder if there's a bad tie rod. I don't have any play in either front wheel though. 2017 Nissan Altima
Basic but very useful info
Wish I could hear this
Good info but audio way too quiet
Does anybody measure runout when the rotor is not attached to the car? How can they measure runout after the rotor is turned or grinded.
Turning the rotor properly cuts the rotor runout to zero. Remounting the rotor allows a remeasure, however, because of stacking variation, (other components mounting the rotor) the total runout may not be zero. Look at other videos for how that is dealt with (shims etc). Good Luck!!
750 Suzuki Do you work on classic cars? I understand that newer cars tend not to have this problem.
I know that it is mentioned as a possibility, but I personally never worry about it, I swap my pads long before turning the rotor is necessary, Classic? 79 pickup; 78 motorcycle, probably not what would be considered classic but they're mine and what I work on.
When you have rotors turned they will have 0 run out. What you would want to do is to check the run out at the hub, just outside of the lugs. If you have no run out then you are good to go. Mount the rotor and it will have no pulsation. If it has more than .001 of run out, then you will have pulsation with the newly turned rotor, if not immediately then after some miles when the rotor bends with the distorted hub. You will need to either use brake align rotor shims to offset the hub run out or get a new hub.
+john joseph What makes my car shake over 55mph?