The GMC M135 was GMC’s design for the 2.5-ton 6×6 truck class that the US Army re-equipped after the Second World War. In the competition that produced the M35, the GMC was classed as substitute standard in the United States but became the standard truck in Canada.
GMC M135 at a glance
| Class | 2.5-ton 6×6 medium truck |
|---|---|
| Era | late 1940s onwards |
| Role in the US | substitute standard |
| Role in Canada | standard 2.5-ton truck |
| Competing designs | Chrysler, GMC, REO and Studebaker |
| Standard US truck | REO-designed M35, later built by several makers |
| Predecessor of the class | GMC CCKW, more than 560,000 built |
| M35 in service | standard until 1990 |
| Replacement of the class | FMTV from 1991 |
Based on one source, the English Wikipedia article on the 2.5-ton 6×6 truck class, which covers the M135 as GMC’s post-war entry. No free photograph of an M135 was found.
History of the GMC M135
The post-war competition
In the late 1940s the US military needed a new standard 2.5-ton truck. Chrysler, GMC, REO and Studebaker all submitted designs, and the REO design was standardised for all services as the M35. The GMC design was classed as substitute standard, receiving the M135 designation in the United States, but it became the standard truck in Canada. The M series had first been fielded in the late 1940s, originally known as the M34 and renamed M35 in 1954.
What the class was
The 2.5-ton, 6×6 truck was a standard class of medium-duty truck designed at the beginning of the Second World War for the US Armed Forces and in service for over half a century, from 1940 into the 1990s. The basic cargo versions were designed to carry a nominal 2.5 short tons over all terrain and in all weather. During the war the most important model for the US Army was the GMC CCKW, of which more than 560,000 were built, while more than 200,000 Studebaker and REO US6 trucks were built mainly for Lend-Lease export, largely to the Soviet Union.
Service and replacement
The M35 became one of the most successful and long-lived series of trucks ever deployed by the US military, used in Vietnam and, with modifications, into the late 1990s, and it remained the standard 2.5-ton truck until 1990. In 1991 the US military began replacing the ten-wheeled 2.5-ton trucks with the four-wheeled, cab-over-engine LMTV variants of the Family of Medium Tactical Vehicles. Half a century after the war, remanufactured M35 trucks still met 95 percent of the performance requirements at 60 percent of the cost of a new FMTV.
Design and features
- Three driven axles: the 6×6 layout shared by the whole 2.5-ton class.
- Off-road rating: the 2.5-ton payload was rated for cross-country use in any weather.
- Standard in Canada: the GMC design was chosen over the US-standard M35 there.
- Long service life: the class stayed in service from 1940 into the 1990s.
- Many bodies: cargo, dump, tractor and tanker bodies were all part of the class.
GMC M135 versions
- GMC M135: the GMC-built 2.5-ton 6×6, substitute standard in the US.
- REO M35: the US-standard truck of the same class.
- M34: the original late-1940s designation, renamed M35 in 1954.
- GMC CCKW: the wartime predecessor of the class, built until 1945.
- FMTV LMTV: the 4×4 cab-over replacement introduced from 1991.
The M135 followed the wartime GMC CCKW in the same 2.5-ton class, and GMC’s civilian trucks of the period included the Blue Chip pickups. More trucks are in the GMC collection.
Sources
- 2½-ton 6×6 truck, English Wikipedia: post-war competition, M135 status, M35 service, class history
