UPS used several inline sixes in their box truck delivery vans- - - -292 Chevy, 300 Ford, and an Onan/Cummins inline turbo Diesel that was about the same length and height as the gas engines. It was rated at 120 HP at 3600 RPM, which I confirmed with a dyno run several years ago. It was originally a generator engine that Cummins inherited when they bought out Onan. UPS needed so many of them for their fleet that Cummins couldn't meet the demand, so Big Brown retrofitted the trucks for a different engine and sold the Onan take-out engines for scrap iron prices. I have one of them stashed away for a future project. The engine is somewhat smaller and lighter weight than the ones used in Dodge pickups.
Jerry
