Title: Inspect and replace companion flange and/or pinion seal; measure companion flange runout.
Course: Automotive Technology III (20104-III) > Section: Manual Drive Train and Axles: Drive Axle Diagnosis and Repair-Ring and Pinion Gears and Differential Case Assembly

Procedures should include

- checking differential yoke for runout
- checking seal
- replacing companion flange and seal, if necessary.

ASE Education Foundation
2017 Automobile Service Technology (AST) Level
III. Manual Drive Train and Axles
E. Drive Axle Diagnosis and Repair
E.1 Ring and Pinion Gears and Differential Case Assembly
Task 4

Process/Skill Questions:

- What are the procedures for replacing the companion flange?
- What tools are used to check runout?
- What failure can result from an improperly torqued pinion nut?