I switch from 8.25X20s to 10.00X22.5s on my 64 GMC the 10.00X22.5s are almost two inches taller than the 8.25x20 tires witch was fine with me it is a lot better on the top end speed of the truck. The switch was also good for a full mile per gallon better mileage too.
The 64 has a little bigger pattern than the older trucks and is still availible through Accuride.

The difference between men and boys is the price of their toys.
Grant from Roy, Washington
1956 6100 Chevy Dump Truck in the Gallery
1964 GMC Drump Truck in the Gallery
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