A freind of mine has a '72 3/4 ton that has a 3.55 gear in it. It's a 350/turbo 400 standard 3/4 ton model, coil spring rear suspension. We checked the codes from the 3rd member against the Chevrolet truck number guide from Cars & Parts. On the 9 1/2' duallies, I've only seen 2 of them, they may have been some sort of aftermarket conversion off a light 3/4 ton, but they did say 3500 on the sides.
