The Stovebolt Site Forums The Shop Area General Truck Talk SPEEDOMETER??

I was looking into getting a speedo for my 54; I have a saginaw trans with 3:42 rear gear ratio so I know the stock speedo wouldnt work. I was wondering where I could find one that would work correctly and have the appearance of the original. I might consider just swapping out all my gauges depending on the cost.

Can't you use the original if you swap the gear in the tranny?

Yes.

I'm running 30.5 tall tires. What gear # of teeth would i need to change to? thanks

I think you need to find a correct pair of "drive" and "driven" gears for the transmission. Good luck.

Or, it costs about $100 to have an adapter made. I did this after changing to a 3.55 rear-end and changing to taller radial tires - it is now within 1/2% accurate at 60 mph.

Speedometer Shop

I ran 4 measured ten-mile segments on an interstate at 60 mph. Sent them the average of the four measurements.