I have a 305-70-16 on my stock 99 f250 diesel.
235/85/r16
You will find that on the drivers door manufacturers sticker.
the horn is on right front side under battery can get see it from tire wall at top back conner
225/35r 20
215/75/15
Lift the car, remove the tire, remove the brake shoes/calipers, remove and dispose of the old pads. Put in the new pads, replace the brake shoe/caliper, replace the tire and lower the car.
235-85 16
265/75-16
The stock tire size for a 4-wheel drive 1975 F250 is 235/75-15, 235 x 733 mm. The bolt pattern is 5x5.5, and the the offset range is -20 to 2.
Other than Legos, the worlds largest tire manufacture is Goodyear.
kangoo69 diesel
your tire pressure will be 30 front 35 back