Contact Pattern Location

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

• Drive pattern on the drive side differential ring gear well centered on the tooth.
• Coast pattern on the coast side differential 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 differential ring gear tooth patterns for all axles.

Fig 1: Identifying Acceptable Ring Gear Tooth Pattern

Courtesy of FORD MOTOR CO.

Correct backlash with a thinner pinion position shim as necessary.

Fig 2: Identifying Thinner Pinion Position Shim Required

Courtesy of FORD MOTOR CO.

Correct backlash with a thicker pinion position shim as necessary.

Fig 3: Identifying Thicker Pinion Position Shim Required

Courtesy of FORD MOTOR CO.

Correct pinion position shim that requires a decrease in backlash.

Fig 4: Identifying Required Decrease In Backlash

Courtesy of FORD MOTOR CO.

Correct pinion position shim that requires an increase in backlash.

Fig 5: Identifying Required Increase In Backlash

Courtesy of FORD MOTOR CO.