I don't have the tool required to set pinion depth, and
don't want to buy it for a one time use. That was the
purpose of my question regarding backlash and pinion
depth. You don't think setting my pinion in 5 or 10 thou
will help me set my backlash properly with the shims
available from Ford?
The pinion depth shim is intended to align it with its
matching ring gear for perfect mesh. The ring gear
shim is used to establish the correct backlash.
Think of the pinion near the ring as a cone near a ramp.
If the ramp angle is 30 degrees for example, the pinion
could be moved .020 axially to bring it .010 closer to
the ramp represented by the ring gear. However, if
this were done, the movement would mismatch the
meshing geometry, leading to higher shear loads,
early wear, and ultimate failure.