Vulcan Rider wrote:
SRockwood wrote:
Rotors should also be turned any time the pads are replaced to allow for proper bedding and reduce chances of noise.
Nope, sorry, I do NOT agree with that.
Turning rotors greatly decreases their life.
Many/most cars being built these days have rotors so thin that trying to turn them creates a safety hazard. Truck rotors might not be that thin......yet.
A couple of minutes with a piece of sand paper in hand is sufficient to break the glaze and help with "bedding".
If the rotors are turned below spec, then they should be replaced. Since you turn rotors to even out surface imperfections and grooves, that life is effectively the same regardless of whether you turn them or not. If they're warped and end up below spec after turning, they should've been replaced anyway. By not turning them to remove imperfections or warping, you're just making it really hard to measure whether or not they're within spec. In other words: if you have a 30mm thick rotor, with a minimum spec of 28mm, they're out of spec if they've got 1.1mm deep grooves on both faces, whether you turn them or not.
Hand-sanding them will just make for an uneven surface.