From Longman Dictionary of Contemporary Englishcrankshaftcrank‧shaft /ˈkræŋkʃɑːft $ -ʃæft/ noun [countable] TTCa long piece of metal in a vehicle that is connected to the engine and helps to turn the wheels
Examples from the Corpus
crankshaft• All moving parts, apart from the plain-bearing crankshaft, use needle roller bearings to help it rev freely.• The Corrado's supercharger sits alongside the transversely mounted engine and is belt-driven off the crankshaft pulley at 1.66 times engine speed.• Until six weeks ago I had first class service, then, suddenly, the crankshaft snapped.• When checked for straightness, this crankshaft was found to have little or no distortion. 