Final answer:
To adjust a drive axle gearset and move the contact pattern away from the crown gear tooth root, the pinion should be moved away from the crown gear. This adjustment ensures proper gear operation and prevents potential gear failure due to stress.
Step-by-step explanation:
When adjusting a drive axle gearset to move the contact pattern away from the crown gear tooth root, the correct action to take is A. Move the pinion away from the crown gear. By moving the pinion gear further away, the contact patch between the pinion gear and the crown gear moves towards the center of the crown gear tooth face, away from the root.
The contact pattern is critical for ensuring the longevity and quiet operation of the gearset. If the contact pattern is too close to the root or the tip of the teeth, it can lead to increased stress and potential failure.
Adjusting the drive axle involves setting the correct pinion depth and backlash, which are both crucial for optimal gear performance. Increasing the backlash would not necessarily move the contact pattern away from the root, similarly, simply decreasing the backlash would not achieve this either; both actions could result in other problems without addressing the contact pattern issue directly.