The m18 hellcat destroyer tank has 76 mm Gun Motor Carriage develops by the American in World War II. The maker to Buick gave it the nickname Hellcat Tank and it was the greatest track non-breakable combating motor vehicle during the war with a top speed up to 60 mph in travelling. Since the tank destroyer had moderately low shield the favorite tactic that its crews used was hit-and-run. Many German Panther and Tiger tanks were destroyed because they could not turn their turrets fast enough to return fire. During light of knowledge gained in North Africa, the 37 mm gun was established to be insufficient and the design was distorted to use a British 57 mm gun. Throughout the development process, the design was further up gunned to a 75 mm gun, and then finally to the 76 mm gun. The Christie suspension requirement was also dropped, and replaced with a torsion bar suspension. While a new proposes the M18 included several ground-breaking maintenance features. The Wright R-975 engine was mounted on steel rollers, which permitted it to be disconnected from the transmission, rolled out onto the lowered engine rear cover, serviced and then reconnected to the vehicle