Contact Pattern Location

In general, desirable ring gear tooth patterns must have the following characteristics:

• Drive pattern on the drive side ring gear well centered on the tooth.
• Coast pattern on the coast side ring gear well centered on the tooth.
• Clearance between the pattern and the top of the tooth.
• No hard lines where the pressure is high.

Acceptable ring gear tooth patterns for all axles. 

Fig 1: Acceptable Ring Gear Tooth Patterns For All Axles

Courtesy of FORD MOTOR CO.

Correct backlash with a thinner pinion position shim required. 

Fig 2: Correct Backlash With Thinner Pinion Position Shim Required

Courtesy of FORD MOTOR CO.

Correct backlash with a thicker pinion position shim required. 

Fig 3: Correct Backlash With A Thicker Pinion Position Shim Required

Courtesy of FORD MOTOR CO.

Correct pinion position shim that requires a decrease in backlash. 

Fig 4: Correct Pinion Position Shim That Requires A Decrease In Backlash

Courtesy of FORD MOTOR CO.

Correct pinion position shim that requires an increase in backlash. 

Fig 5: Correct Pinion Position Shim That Requires An Increase In Backlash

Courtesy of FORD MOTOR CO.