My guess is if the contact pattern looks good (should, as it wore to where it is now) then just keep on running it.

If gear pattern looks like it could be corrected then you might be able to do so while also reducing backlash.

Also check that bearings are in good shape and snug enough per the manual. Might need adjustment if they're worn but appear in good useable shape.

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-