Bob,

I also have the cpp disc brake setup although my truck is a 1940 it has 1955 1st series axles front and back. The OEM 16 inch rims fit over the caliper just fine. However not everything does. Check your own setup but mine measures over 13 inches at the widest part of the caliper. So the center of any wheel you get has to be like 13 1/2 inches in diameter. I have 16 inch artillery wheel with a 13 1/2 inch center and have to run one of the cpp spacers between the wheel and the rim so the flange on the artillery wheel will clear the caliper.

As far as back spacing goes the original rim is almost centered on the hub. I believe there is about 3/4 of an inch difference between the front spacing and the back spacing. So a 6 inch rim (actually 7 inches wide when you add in the lip) would probably have a 3 1/2 to 4 inch backspace.

The other issue you have to look at is whether the tie rod end is inside the 13 or so inch diameter of the disc break. If your truck is not lowered it probably is inside the diameter of the brakes. If it is inside the tire and rim won't interfere with the steering arm or tie rod. If you are using lowered spindles or a dropped axle, the tie rod end could be outside the rim area and then you need to find out how much distance between the mounting surface and the tie rod. That could limit your rim and tire width or your backspacing.

Bill Schickling

1940 1/2 ton, 1940 3/4 ton
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