We’ve seen a lot of GM’s Advance Design Trucks (1948-1955) here over the years. But this one, posted by Eric Clem, is rather exceptional, as 1953 was the first year that GM’s Hydra-Matic four-speed fluid-coupling automatic transmission was available on GMC’s civilian ½, ¾, and 1 ton trucks. It was of course very well proven by then, given its use in armored vehicles in WW2 and in the post-war M153 2.5 ton 6×6 Army truck, never mind hundreds of thousands of passenger cars. One wonders why it took so long.
Well, it was expensive, and most trucks were bought with operational economics in mind. But GM was convinced there were advantages that outweighed the cost. And that applies not just to light trucks, but heavy duty ones as well, as they also introduced an 8-speed Hydra-Matic as well as an even more complex 13-speed Twin Hydra-Matic for heavy duty trucks. A post on them is coming shortly.
Here’s a proper look at what we’re talking about: it appears to be a 3/4 ton, 8′ bed pickup, which would have had the 228 cubic inch version of the highly regarded GMC inline ohv six.
This truck obviously had a former life (or two) as a working truck, as they almost inevitably did back then. Tree work and spraying, by A.H. Hembree—call WA·6·1246.
The Truck Hydra-Matic gear selector is just visible in this crop.
Here’s what that looked like, thanks to a shot from the web.
First again…yes, in terms of offering an automatic on a wide range of light trucks. But for the record, Ford did also offer its Fordomatic in 1953, but only on the 1/2 ton F100. Chevrolet started offering the Hydra-Matic in 1954.
But that was just for the light trucks. In mid-year 1953, GMC started offering the 8-speed Hydra-Matic, which had a two-speed reduction unit to yield the eight speeds in 4-5 ton trucks. The four speed was actually standard in the delivery van.
The basic 4-speed Hydramatic continued to be available on Chevy pickups through 1960, and GMC pickups through 1963, replaced in both by the cheaper and simpler Powerglide.
That’s the (sort of) full load on the Hydra-Matic’s utilization on pickups and light trucks, but a more detailed look at some of the exotic 8-speed and Twin Hydra-Matics is on the way.