3.07 differential

[Jcrosby (Jeffrey Crosby)]

Good discussion here:

Speedometer Gear Ratio Adaptor installed. Was Speedometer Cable Nut Size?

I’ve been doing research on gear reduction units to alter the indicated speed if you change rear end ratios. No place I’ve talked to makes a ratio adaptor unit that attaches to the back of the speedometer or attaches to the angle drive. The ratio adaptor units I’ve found all use 5/8" X 18 threads of 3/4" threads. The angle drive and speedometer are about 1/2" . The only way to change the speedometer reading, short of replacing the speedometer itself is to send your speedometer cable to a sh…