Voyager V6-3.0L VIN 3 (1998)
Brake Rotor/Disc: Testing and Inspection
GENERAL INFORMATION
Any servicing of the rotor requires extreme care to maintain the rotor to within service tolerances to ensure proper brake action.
Before refinishing or refacing a rotor, the rotor should be checked and inspected for the following conditions:
Braking surface scoring, rust, impregnation of lining material and worn ridges.
Excessive rotor lateral runout or wobble.
Thickness variation in braking surface of the rotor (Parallelism).
Dishing or distortion in braking surface of the rotor (Flatness).
If a vehicle has not been driven for a period of time, the rotors will rust in the area not covered by the brake lining and cause noise and chatter
when the brakes are applied.
Excessive wear and scoring of the rotor can cause temporary improper lining contact if ridges are not removed from braking surface of rotor
before installation of new brake shoe assemblies.
Some discoloration and/or wear of the rotor surface is normal and does not require resurfacing when linings are replaced.
Excessive runout or wobble in a rotor can increase pedal travel due to piston knock-back. This will also increase guide pin bushing wear due to the
tendency of the caliper to follow rotor wobble.
Thickness variation in a rotor can also result in pedal pulsation, chatter and surge due to variation in brake output. This can also be caused by
excessive runout in the rotor and/or the hub.
Dishing or distortion can be caused by extreme heat and abuse of the brakes.
CHECKING ROTOR FOR RUNOUT AND THICKNESS
NOTE: The procedure for checking rotor runout and thickness is the same for the front and rear rotor. If there is a specification difference between
the front and rear rotor it will be designated as such in the specifications of the following procedure.
Checking Brake Rotor For Runout
On-vehicle rotor runout is the combination of the individual runout of the hub face and the runout of the rotor. (The hub and rotor run-outs are
separable). To measure runout on the vehicle, remove the wheel and reinstall the lug nuts tightening the rotor to the hub. Mount Dial Indicator,
Special Tool C-3339 with Mounting Adaptor, Special Tool SP-1910 or equivalent on steering arm. Dial indicator plunger should contact braking
surface of rotor approximately 10 mm (0.393 inch) from outer edge of rotor. Check lateral runout on both sides of rotor. Lateral runout of the
rotor should not exceed 0.13 mm (0.005 inch).
