Diyvehiclerepair
ABSTRACT. Brake disc runout, which is defined as a variation in the distance of a brake surface to a reference plane, is a key contributor to torque variations. Runout also leads to disk thickness variation by inducing uneven wear of the disc and is affected by assembly and manufacturing inconsistencies.
- What causes disc runout?
- What is maximum disc run out?
- What is the minimum disc run out?
- What causes rotor lateral runout?
- What tool is used to measure disc run out?
- What happens if a rotor is too thin?
- How thick should disc brakes be?
- What is acceptable wheel runout?
- What does radial run out mean?
What causes disc runout?
What could have caused the lateral runout? The causes of the condition range from lugs that were over or unevenly torqued to common corrosion between the hub and rotor. There are other causes, such as the rotor machined to less-than-minimum thickness and overheating.
What is maximum disc run out?
To confirm that the brake disc is in alignment, a run out measurement was taken to eliminate the brake disc as a source of misalignment. The maximum amount of tolerance for brake disc runout is >0.08mm.
What is the minimum disc run out?
A runout of 0.0005 inch (0.00254 mm) at the bearing flange could result in a 0.001 inch (0.025 mm) runout at the rotor friction surface. The maximum allowable runout at the rotor friction surface is 0.002 inch (0.050 mm) as stated by most manufacturers.
What causes rotor lateral runout?
Lateral runout results from uneven lug nut torque and damaged studs or debris between the hub and rotor. A rotor can often be resurfaced to correct this variance.
What tool is used to measure disc run out?
A 3 piece kit designed specifically to allow a DTi gauge to be mounted securely in almost any position against the brake disc to measure disc warp. DTi gauge accurate to 0.01mm, total deflection 10mm.
What happens if a rotor is too thin?
When a rotor is too thin, it overheats and warps, leading to an annoying vibration or pedal pulsation. When rotors were thicker, they could take the wear from the brake pads, be machined and still have enough metal left to dissipate the heat.
How thick should disc brakes be?
Ideally, your brake pads should be thicker than 6.4 mm (¼ inches) for proper functioning. If it's thinner than this, consider getting a replacement soon. Most car mechanics also agree that the bare minimum brake pad thickness is 3.2 mm (⅛ inches).
What is acceptable wheel runout?
The maximum suggested radial runout for a rotating tire/wheel assembly is . 125 inches for both front and rear tire positions.
What does radial run out mean?
Radial runout involves distance discrepancies from one point to another. The greater this discrepancy, the more it will cause the wheel to bounce up and down as it rotates. This bouncing causes the vibrations that often travel up through the steering column, becoming noticeable inside of the car.
