Trackside Classic: The VW Bus’ 2200 HP Big Brother – And It Had Four Mechanical Gears Too

(first posted 6/26/2012)    Germany’s definitive high-speed diesel locomotive, the V200, appeared in 1953, three years after the black-over-red VW Samba. Coincidence? It was a bit better powered than the VW bus, packing two high-speed turbocharged (1500 rpm) V12 diesels by either Daimler-Benz or Maybach, which gave it a top speed of 140 kmh (85 mph). That was in fourth gear. Yup; these were not diesel-electric locomotives, but sent their power through a torque converter and four mechanical gears, a system called “Mekhydro” for mechanical-hydraulic.

Contrary to popular belief, American diesel locomotives aren’t diesel-electric because it’s the most efficient way to transfer the engines’ power to the wheels, but because it’s simpler, more familiar, and requires less service, although the V200 did have an excellent reliability rep. And the diesel-electric drive allows better control of slippage, especially with modern electronic controls. That’s a critical function on take-off with today’s super-power locomotives.

Actually, there were two distinct versions of  drive systems. Maybach supplied the Mekhydro, with a single torque converter and four mechanical gears, power-shifted automatically. Voith supplied a more complex (and smoother-shifting) “Turbo” transmission that incorporated three different torque converters in a rather complex arrangement.

The V200 wasn’t the first (or last) of this series of modern German diesel hydraulic-mechanical locomotives. But it was the most popular, perhaps in part to it’s VW bus styling. And the Voith transmission didn’t just stay in Germany either.

In 1960, the V200’s builder, Krauss-Maffai, built a larger 4000 hp locomotive using the Voith Turbo transmission and two Maybach V16 engines, targeting the US market specifically. The ML 4000 was much more powerful than the typical US diesel-electric locomotive, and stunned the industry. Southern Pacific and the Denver & Rio Grande Western were the first customers.

They didn’t do so well in the mountainous stretches, but served reliably on the flats, with only one recorded failure. ALCO also built a locomotive with the Voith transmission, the DH643. But EMD (GM) and GE got the message, and quickly turned out more powerful diesel-electric locomotives. The KM’s were soon phased out, as the railroads preferred to keep maintenance simple and around one (familiar) technology.

Oh, and the V200 had a little railroading brother too.