Driving the Mercedes around in the winter wonderland that has become the eastern Puget Sound, I've discovered an odd, and unusually immobilizing, feature on the Mercedes.
But, some background is required. The Mercedes is equipped with an automatic transmission, which, instead of a clutch, is fitted with something called a torque converter. The torque converter is the thing which allows the engine to spin at a different speed as the transmission and so thus, not kill the engine anytime you come to a stop.
When someone designs a torque converter, they design in a parameter called the stall speed, above which the engine may not turn while the wheels are locked in place. The stall speed of the Mercedes' torque converter is really low—like 400rpm low—which means that the engine really fights the brakes while stopped.
Normally, this isn't a problem. It just means that you really need to stand on the brakes to keep the car at a standstill. But if you're on a slippery surface, it means that as you slowly let off the brakes, the rear wheels will start to spin long before the front wheels let go.
Well, shit.
This essentially means that every time I stop on ice, I'm guaranteeing that I won't be able to roll away without spinning the real wheels—without, of course, doing something stupid like using the parking brake...which doesn't really work all that well, anyway. Lovely.
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