WE DRIVE THE 1944 BUICK M18 HELLCAT TANK DESTROYER

n honor of ... well, because it's a cool story, we're revisiting this June 2013 tale of the time we drove a Buick tank. Really!

Over its 110 years as an automaker, Buick has been through a lot -- Prohibition, the Great Depression, oil embargos, bankruptcy, and even two World Wars. Like many Americans and American companies during World War II, Buick contributed heavily to the war effort. Not only did the Buick Motor Division of GM churn out ammunition and engines for the Army Air Force's B-24 bombers, but they also contributed by designing a completely new class of fighting vehicle -- the now-legendary M18 Hellcat tank destroyer -- designed to punch back against Hitler's panzer tanks. It was one of the fastest tracked vehicles ever produced.

The Buick M18 Hellcat does resemble a tank, but history buffs are quick to point out, it's actually a tank destroyer (TD) -- a now-defunct U.S. Army armor class. Back in the early '40s, doctrine dictated that well-armored tanks, like the Chrysler-built M4 Sherman medium tank, were to be used solely to support infantry assaults and cause havoc behind enemy lines, whereas destroyers like the Hellcat were supposed to use their speed and maneuverability to flank the enemy and destroy its armor before high-tailing it out of the danger zone.

With the war gearing up, early TDs were rushed into service, using existing platforms as the jumping off point. For example, the M3 TD was a halftrack with a 75 mm gun mounted on it, the M6 was a Dodge WC pickup with a 37 mm gun, and the M10 was essentially a Sherman tank with an open turret and paper-thin armor. The architects of the tank destroyer doctrine weren't at all happy with the improvised designs (and neither were Army generals like George S. Patton, who argued that the Tank Destroyer would "just become another tank") and pushed for a ground-up TD design.

That design would ultimately become the M18. With the tank destroyer motto of "Seek, Strike, Destroy!" in mind, Buick was tasked with building the Army a prototype. Its design studio, under the tutelage of legendary automotive designer Harley Earl, went to work in the fall of 1941, mounting a closed turret with a 57mm gun onto the chassis of a light tank. Though transmission problems limited top speed to just 38 mph, the Army saw some potential in Buick's design and ordered two prototypes. With word of the thick frontal armor of the German panzer spreading, the Army ordered Buick to fit a larger 76 mm gun to one of the prototypes, and because of packaging and weight constraints with the new gun, Buick fit the new prototype with an open-topped turret. But the Army still wasn't satisfied -- they wanted more power out of its new tank destroyer, so Buick yanked its own engine out, and replaced it with a monstrous 16.0-liter supercharged radial nine-cylinder engine. Called the Continental R975 and found in the Sherman tank and aircraft like the Ford TriMotor, the engine made 400 hp and 940 lb-ft of torque, and was paired with a three-speed "Torqmatic" automatic transmission, giving the TD a top speed of 60 mph.