Thread: Name this part

I can help.
What it does is convert the speedo to the true road speed when hi/lo is selected in the 2 speed diff.
If you are new to 2 speed diffs you have a monkey in the diff,monkeys love bananas
Andrew

Originally Posted by Sprint

A friend recently acquired a early 50's F series truck, and this little item has us stumped.....

Vehicle: Early 50's Ford F-series
Drivetrain: Flathead V8, 4(?) speed manual gearbag and an Eaton 2 speed differential
Part location: In line with the speedo drive cable, screwed to the firewall
Relevant information: I suspect it has something to do with the 2 speed diff, some of the wiring disappears down in the direction of the top of the 'box, and looks the same as the wire going to the 2 speed diff switch on the shifter

It's the ratio changer for the speedometer. A little gearbox. Change the diff and it engages (or disengages) so the correct speed is displayed.

Bob

Andy beat me to it

I could have sworn that was an early attempt at a flux capacitor

figured it was either a ratio corrector for the speedo, or a device to lock out the diff ratio selector while moving.....

any idea when Eaton stopped putting "Eaton 2 speed" plaques on the back of thier diffs?

Originally Posted by It'sNotWorthComplaining!

I could have sworn that was an early attempt at a flux capacitor

No, it is a Calvin & Hobbes Transmogrifier.

Landy Andy is correct it is the speedo ratio change box used with two speed axles.