Otto, There is an existing Tech Tip: Speedometer Rebuild for GM Art Deco Truck (1941-1947 1st series Chevy/GMC), by Jeff Erickson, that might give a little insight on your speedo internals. If you want to try and really get down in the dirt and work on yours to see if it can be repaired, check out this 1952 United Motors AC Bulletin covering speedometers and tachometers. Although the scan quality is a little fuzzy, it's clear enough for me with my tri-focals to read and see how everything goes together and what needs what when repairing a speedo.

I found this resource in a long ago thread on your topic that also has some other useful tidbits you may want to read. Thanks to the fellow Bolters that previously posted this info! thumbs_up

Last edited by Peggy M; 06/04/2024 5:30 PM.
~ Dan
1951 Chevy 3 window 3100
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"My Grandpa Carl's Truck and How it Became Mine"
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