The iterative setup job for a ring and pinion or other bevel set: paint the teeth, roll them, read the pattern on drive and coast sides, then change the pinion shim or carrier adjusters and repeat. Pinion depth moves the pattern toward top or root, backlash moves it toward heel or toe. A well-set pattern is the difference between a quiet axle and one that howls.
Took four tries to set the pattern on that axle, the shim kit was missing the three-thou shims.
Change one thing at a time and write it down; moving shim and lash together hides which move did what.
Also heard as
- setting up gears
- gear setup
- read the pattern
Related terms
Contact pattern
The imprint left on gear teeth by marking compound after running, showing where and how the teeth touch.
Pinion depth
How far the hypoid or bevel pinion sits along its axis toward the gear, set with shims behind its bearing.
Bluing
Shop word for marking compound brushed on gear teeth to read the contact pattern after running.
Ring and pinion
Shop name for the hypoid final drive in a vehicle axle, named by its ratio, such as 3.73 or 4.10.