I'm having issue with run-out!
Typically I do not put a run out gauge on turned Rotors or new OEM. But decided to in this case, on just one to start with. Well ended up put run-out dial gauge on all. Procedure is to remove rotor and turn to new position on hub, if out of spec, or just wanting to hit the sweet spot (closes to zero). This is time consuming to say the least.
I just had a near new set of NAPA rotors turned. I would never buy these myself for a 100 series. But since they were install by PO less than 2k miles ago along with NAPA pads, by Midas. I decided to replace PADs with OEM and just have the rotors turned to make sure true and had good bedding surface for new pads. I did not do a good run-out inspection beforehand. Other than, just put dial gauge on 1 front rotor. Found it out of spec, without really marking each few degrees, to get a good reading. I saw hot spot, imperfection along with bed in rust in spots. So just had all turned.
What I found after have machine turned off vehicle. Was all rotor out of spec. With rears I did remove each rotor from hub and turn to all 5 position. Closest I could get was 50% above max limit out of the spec.
Each side rotor run-out was near the same, more out on rears than fronts. But pattern the same. I'd get 0.00 mm (zero) for about 20 degrees of 360 degrees. Than as I continued to turned rotor 360 degrees. Run-out would start increasing form zero to peak of ~0.25 to 0.27mm at ~ 180 degree point of 360 degrees of disk surface. Than start dropping back to zero as I continued to turn to starting point. Very symmetrical pattern from one side to other side of vehicle, numbers near a match also. Also ran up back side rotors (back disk), which matched front disk (opposite numbers).
Now since they're all freshly turned, it cannot be uneven deposits of pad material or uneven metal surface of disk right!
So questions I have:
Is the brake lath in need of calibration?
Is it's attachment to hold rotors in lath issue?
Is it lathe operator error?
Is it the rotors themselves, can't be trued-up as axis is off?
Or what?
Typically I do not put a run out gauge on turned Rotors or new OEM. But decided to in this case, on just one to start with. Well ended up put run-out dial gauge on all. Procedure is to remove rotor and turn to new position on hub, if out of spec, or just wanting to hit the sweet spot (closes to zero). This is time consuming to say the least.
I just had a near new set of NAPA rotors turned. I would never buy these myself for a 100 series. But since they were install by PO less than 2k miles ago along with NAPA pads, by Midas. I decided to replace PADs with OEM and just have the rotors turned to make sure true and had good bedding surface for new pads. I did not do a good run-out inspection beforehand. Other than, just put dial gauge on 1 front rotor. Found it out of spec, without really marking each few degrees, to get a good reading. I saw hot spot, imperfection along with bed in rust in spots. So just had all turned.
What I found after have machine turned off vehicle. Was all rotor out of spec. With rears I did remove each rotor from hub and turn to all 5 position. Closest I could get was 50% above max limit out of the spec.
Each side rotor run-out was near the same, more out on rears than fronts. But pattern the same. I'd get 0.00 mm (zero) for about 20 degrees of 360 degrees. Than as I continued to turned rotor 360 degrees. Run-out would start increasing form zero to peak of ~0.25 to 0.27mm at ~ 180 degree point of 360 degrees of disk surface. Than start dropping back to zero as I continued to turn to starting point. Very symmetrical pattern from one side to other side of vehicle, numbers near a match also. Also ran up back side rotors (back disk), which matched front disk (opposite numbers).
Now since they're all freshly turned, it cannot be uneven deposits of pad material or uneven metal surface of disk right!
So questions I have:
Is the brake lath in need of calibration?
Is it's attachment to hold rotors in lath issue?
Is it lathe operator error?
Is it the rotors themselves, can't be trued-up as axis is off?
Or what?
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