And I'm not sure on gear ratio for axle I know it came off a 89 f800 jus figured it was close to same as my 85 f600 which is a 2 speed but can go 60mph so that's a plus but could be jus cuz it has the 9-20 tires and my c50 has 8.25-20 cuz from what I have learned here bigger tires get you going faster in big trucks.
