Chrysler's tooling would have been better spent building gearboxes for more reliable engines.
But the Multibank was reliable, despite its complexity
In a competitive test at Aberdeen which began October 11, 1943, and continued until February 10, 1944, four M4A4 tanks with Chrysler multibank engines were entered against four tanks of each of three other engine types. Three of the four Chrysler-powered tanks completed the 4,000 mile marathon. Of the other twelve, only one finished. Ordnance reported that the Chrysler motor gave the most reliable performance, that its maintenance requirement was lowest, its power loss after 400 miles negligible. Its oil consumption was bettered only by a Diesel tank engine.
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