Adjustments Affecting Tooth Contact

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The following 2 adjustments affect the tooth contact pattern:

Backlash adjustment
Pinion depth adjustment

The effects of bearing preloads are not readily apparent on hand-loaded tooth contact pattern tests. However, bearing preloads should be within specifications before proceeding with backlash and pinion depth adjustments.

Pinion Depth Adjustment

Adjust the position of the pinion by increasing or decreasing the distance between the pinion head and the centerline of the ring gear. Decreasing the distance moves the pinion closer to the centerline of the ring gear. Increasing the distance moves the pinion farther away from the centerline of the ring gear.

Backlash Adjustment

Adjust the backlash by means of moving the side bearing adjuster sleeves which move the case and ring gear assembly closer to or farther from the pinion. Also use the adjuster sleeves in order to set the side bearing preload.

If the left side adjuster sleeve is moved in, along with an equal outward movement of the right side adjuster, the backlash will increase.
If the left side adjuster sleeve is moved out, along with an equal inward movement of the right side adjuster, the backlash will decrease.