What is preload on a differential?
Differentials: Side Bearings Proper preload keeps the case from wobbling inside the carrier and adjusts backlash between the ring and pinion gear. Side bearing preload adjustment is crucial to the differential’s operation.
How important is pinion bearing preload?
A slight preload bearing setting assures that proper gear tooth contact is maintained between the pinion and ring gear. This minimizes gear wear and extends the tooth life of both gears. Debris in the axle system is reduced when gear wear is minimized.
Why preload is required?
Why Preload? The purpose of preload in a bearing system is to eliminate clearance that is designed into standard ball bearings. Almost all radial ball bearings are made with a clearance or space between their components to allow for free movement.
What can happen if the pinion bearing preload was set incorrectly?
The pinion gear rotates at driveshaft speed and can mimic a driveshaft speed-related vibration. Improper pinion bearing preload can cause what appears to be a pinion seal leak, but the seal is fine, the pinion gear is moving vertically, horizontally, or diagonally as is rotates.
How much backlash should a diff have?
Keep the backlash variation under 0.005″ if possible. In a perfect world no variation would be the goal. However, even with a straight case the backlash can vary 0.005″ without any negative consequences, so this is an area where each assembler will have to decide how much they are willing to allow.
How much play should a pinion gear have?
008″ to . 013″. There is no spec on amount of play at the driveshaft, it is measured at the teeth of the ring gear while holding the pinion stationary. As for gear noise… with 4.10 you will normally get more noise because of the steeper gear ratio (cost of performance).
What does pinion preload mean?
Pinion bearing preload is measured in inch-pounds and is a measure of the rolling resistance of the pinion bearings after proper torque has been applied to the pinion nut. Set the preload carefully (see “Specifications”) so that the bearings will have a long life.
Why is backlash needed in a rear axle?
The gap is necessary so that the driver or electronics can engage the gears easily while synchronizing the engine speed with the driveshaft speed. If there was a smaller clearance, it would be nearly impossible to engage the gears because the teeth would interfere with each other in most configurations.
How do you set pinion depth?
Note: When adjusting pinion depth, begin with a starting shim stack and make large adjustments at first (10-20 thou) until the correct setting is bracketed; then make progressively smaller adjustments until the final setting is achieved. Adding or subtracting a single shim of one thou can, and does, make a difference.
How is preload adjusted?
There are basically two principal methods to adjust preload: individual adjustment and collective adjustment. With individual adjustment, each bearing arrangement is adjusted separately using nuts, shims, spacer sleeves, crush sleeves, etc.