I have a 76 f700 with a 3208 cat I'm using as a donor truck for a 77 f600 crewcab. I'm trying to find the rear axle ratio and see if I can use it or should change the gear ratios. vin is K70BVA85722, wb 212, color 3x, type K707, body 4A8, trans 6, axle F0N, dso 16, gvwr 27500. thanks for any help

 

K70 = F700 Diesel.

B = Caterpillar model V190-3208 636 cid V8 Diesel.

V = Kentucky Truck Assembly Plant.

A85722 = 1976 Numerical Sequence of Assembly, the trucks specific serial number.

212" Wheelbase.

3X: 3 = Tan / X = Tan.

K707 = F700 Diesel, 27,500 lbs. GVWR

4A8: 4A = Black Heavy Duty Vinyl-Full Width Seat / 8 = 81A Standard Cab.

6 = Clark model 390V 5 Speed Direct.

F0N: F0 = There is no rear axle code of F0 or FO .. it could be FC or FG or FQ or? / N = Ford 9,000 lb. Capacity Front Axle with Power Steering.

27,500 lbs. Gross Vehicle Weight Rating.

16 = Philadelphia PA Ford District Sales Office, where the original selling dealer ordered the truck from.

 

Go to that rear axle and post up all the numbers from any data plate or stenciled numbers from the center casting.

 

Any open rear axle ratio can easily be determined by elevating one wheel, mark d/shaft pinion so rotations can be counted, turn the wheel TWO revolutions exactly, count the d/shaft turns. Helps to have two people. Example; two turns of wheel, little more than 4 1/2 turns of d/shaft = 4.56.