Originally Posted by Bigdreamer
...I haven't found a speed calculator for 10.00 20 tires ...
Try this.
http://www.onlineconversion.com/bigger_tires.htm
OD on a 10.00x20 is about 40" depending on brand and wear.

•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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