Whether it is meant as a complement or to be derisive to American cars, it is not uncommon for a Buick to be referred to as a “tank.” This is usually a reference to their large size or robust construction, but there was a time when Buick actually built a tank– and was one of the fastest tanks of its day.

In the December of 1941, D-Day was still years away, but the United States was preparing for war. Many of the tanks and planes utilized by the U.S. Military did not appear ready to take on the advanced weaponry from the Germans. Throughout America, factories typically used to build cars and trucks were being repurposed for tanks and planes.

The Ordinance Corps put out a demand for a fast-attack tank to be able to compete with the German tanks, and be fast enough to outmaneuver and outflank the opponent. The original requirement called for a torsion bar suspension, 37mm gun and a Wright/Continental R-975 engine.

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Around this time, General Motors committed itself to the War Effort. Harley Earl, one of America’s most influential car designers (Earl brought us the tail-fin), was commissioned to design a tank to meet these requirements. Earl would also develop camouflage for the U.S. Military.

Earl’s staff built a tank with a torsion bar suspension that, despite weighing 20 tons, could move at speeds up to 60 mph. That is even fast for today’s standards. The M-18 or “Hellcat” tank was powered by an aircraft-type engine making 450 horsepower, mated to a three speed hydramatic suspension.

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Its high speed allowed it to outflank the German tanks in battle, and the high road speed proved useful in the Battle of the Bulge. Before the European campaign, the Hellcat was used in North Africa, where the main gun was increased to first a British 37mm gun, then a 75mm unit, before finally ending up with a 76mm main gun, which would be the configuration for the rest of the War, including European and Pacific operations.

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The Hellcat was produced up until October of 1944. Just over 2,500 M18 Hellcats were built, and each was constructed for less than $60,000, which made the pencil-pushers in Washington happy. To this day, the Hellcat is still one of the fastest tanks ever built. Even modern battle tanks like the M1 Abrams are limited to a top speed of 60 mph. So while road going Buicks might not be considered speed demons, when they build tanks– it’s a whole different story.

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