Sounds like "Motor Wheels" a brand and design of wheels that GMC used along with other truck manufacturers, REO being one other make. For the 1.5 and 2 ton trucks GMC most commonly used the same wheels used on a Chevy, usually made by Kelsey Hays, 5 lug fronts and 10 lug rears, but same wheels front and rear.

If you have 5 lugs both front and rear then you have Motor Wheels. They are hub piloted. You may find a stamp near the center of the wheel with the manufacturer's name.

Post the bolt circle dimension, and the center hole size, and I'll do some checking. I think we will find that you don't have any modern tubeless wheel options..

Look at this Tech tip for a little info in wheels all together, but not about Motor Wheels http://www.stovebolt.com/techtips/wheels/

This Accuride catalog has most all the wheels and bolt patterns listed that are still available new for big trucks. You may find something that will work?
http://www.accuridewheels.com/completeversion.pdf

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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