OK guys... My plan for now is as follows.
0. The noises that I have are of two distinct kinds, a whining noise
that appears when I ease the gas pedal, and grinding noise that I hear
at low speeds.
1. I received the adjuster lock tab replacement from the dealer.
2. I will take off the diff cover again, and will try to adjust the
adjuster lock to reduce backlash to spec, using a dial indicator to
measure backlash. I hope (and would like you to confirm) that I can do
it using a screwdriver through the access hole.
3. If I cannot get a screwdriver through the hole, I could pull the
axle, and make a tool that goes through the axle hole and turns the
adjuster. I would make it out of some materials, I have a welder. What
I will need to know is dimensions of the tool (ie where to place the
4. After I do that, I will drive around to verify that the whining
noise is gone. If not, I will take the truck to a dealer. I realize
that the grinding noise at low speeds may remain, could be due to
5. If the whining noise is gone, I will take the diff apart and
replace the bearings that may have caused the grinding noise. I am
not, yet, sure whether it is easy or not to put it back together
Does this plan make sense?