- Weight: 12,300 pounds
- Size (LxWxH): 269" x 88" x 105"
- Max Speed: 58 mph
- Range: 300 miles
When Reo Motors with its G-742 (M34/M35 cargo trucks) was selected as the prime contractor for the “interim” series of trucks to replace the Army’s aging fleet of CCKWs in 1949, GMC was dismayed. The company responded by submitting a prototype of its own design, built with corporate money, as an alternative. In its original form it had much in common with the CCKW, and this was a much-touted advantage. Many of the repair parts were already in place in the Army’s supply channels and a minimal amount of new training would be required for mechanics.
Its most radical departure from the previous generation of vehicle was the installation of GM’s Hydramatic transmission. The transmissions in these trucks had a rear pump. This allowed the truck to be pull-started in a conventional manner, something that can’t be done with today’s automatics.
The earliest trucks, the M135s, had 11.00-20 single rear tires for improved off-road performance.
The transmissions in the very first trucks shipped to Korea during that war were deficient. These problems were almost immediately corrected, but not before the transmissions earned an unwarranted reputation that lingers to this day.
Though these trucks did not garner the widespread acceptance with the U.S. Army that GM had hoped for, they did with the Canadian armed forces, where they formed the backbone of military transport for more than 30 years.