| Table 1: | Pattern Evaluation (Ring Gear) | 
Drive Side  | Coast Side  | Pattern Condition  | Corrective Action  | ||||||
|---|---|---|---|---|---|---|---|---|---|
Heel Toe  | Toe Heel  | ||||||||
 
 
  | |||||||||
 
 | 
 
 | Drive Side Centered - Coast Side Centered  | No correction required.  | ||||||
Drive Pinion Issue - 2-Cut Gearset  | |||||||||
 
 | 
 
 | Drive Side Low Heel Contact - Coast Side High Heel Contact  | 
  | ||||||
 
 | 
 
 | Drive Side Low Heel Contact - Coast Side Low Toe Contact  | 
  | ||||||
Backlash Issue  | |||||||||
 
 | 
 
 | Drive Side High Heel Contact - Coast Side High Toe Contact  | Backlash incorrect. The ring gear is too far away from the drive pinion. Inspect and adjust the backlash as necessary to ensure that it is approximately 0.08-0.13 mm (0.003-0.005 in).  | ||||||
 
 | 
 
 | Drive Side Low Toe Contact - Coast Side Low Heel Contact  | Backlash incorrect. The ring gear is too close to the drive pinion. Inspect and adjust the backlash as necessary to ensure that it is approximately 0.08-0.13 mm (0.003-0.005 in).  | ||||||
 
 | 
 
 | Drive Side Centered - Coast Side Centered  | No correction required.  | ||||||
Drive Pinion Issue - 5-Cut Gearset  | |||||||||
 
 | 
 
 | Drive Side High and Slightly Heel Contact - Coast Side High and Slightly Toe Contact  | 
  | ||||||
 
 | 
 
 | Drive Side Low and Slightly Heel Contact - Coast Side High and Slightly Toe Contact  | 
  | ||||||
Backlash Issue  | |||||||||
 
 | 
 
 | Drive Side Heel Contact - Coast Side Toe Contact  | Backlash incorrect. The ring gear is too far away from the drive pinion. Inspect and adjust the backlash as necessary to ensure that it is approximately 0.08-0.13 mm (0.003-0.005 in).  | ||||||
 
 | 
 
 | Drive Side Toe Contact - Coast Side Heel Contact  | Backlash incorrect. The ring gear is too close to the drive pinion. Inspect and adjust the backlash as necessary to ensure that it is approximately 0.08-0.13 mm (0.003-0.005 in).  | ||||||
Drive Side Heel Toe  | Pattern Condition  | Coast Side Toe Heel  | Pattern Condition  | Corrective Action  | 
|---|---|---|---|---|
Face Hobbing  | ||||
 
 | Toe Contact  | 
 
 | Heel Contact  | Pinion shim correct. Increase backlash.  | 
 
 | Desirable Pattern - Drive pattern should be centered on tooth  | 
 
 | Desirable Pattern - Coast pattern should be center to slightly toe on tooth  | No correction required.  | 
 
 | Top Toe Contact  | 
 
 | Top Heel Contact  | Backlash correct. Increase in pinion shim.  | 
 
 | Root Heel Contact  | 
 
 | Root Toe Contact  | Backlash correct. Decrease in pinion shim.  | 
 
 | Top Heel Contact  | 
 
 | Top Toe Contact  | Pinion shim correct. Decrease backlash.  | 
 
 | Root Toe Contact  | 
 
 | Root Heel Contact  | Pinion shim correct. Increase backlash.  | 
Face Milling  | ||||
 
 | Desirable Pattern - Drive pattern should be centered on tooth  | 
 
 | Desirable Pattern - Coast pattern should be center to slightly toe on tooth  | No correction required.  | 
 
 | Top and Slightly Heel Contact  | 
 
 | Top and Slightly Toe Contact  | Backlash correct. Increase in pinion shim.  | 
 
 | Root and Slightly Toe Contact  | 
 
 | Root and Slightly Heel Contact  | Backlash correct. Decrease in pinion shim.  | 
 
 | Heel Contact  | 
 
 | Toe Contact  | Pinion shim correct. Decrease backlash.  |