America’s Indestructible Engine: The Forgotten Empire of Detroit Diesel

From WWII landing craft and Sherman tanks to city buses, tugboats, and construction equipment, Detroit Diesel’s two-stroke engines helped power the modern American world — and became famous for being compact, modular, and nearly impossible to kill.

In this video, we trace the forgotten origins of General Motors’ bold 1938 decision to “shrink diesel” for mass production, and why the Series 71 became the legend mechanics called the “Screaming Jimmy.” You’ll learn what made these engines different (two-stroke power delivery, the Roots blower, unit injectors, and standardized cylinder design), how they proved themselves in brutal wartime conditions, and why emissions rules and shifting industry demands eventually pushed Detroit Diesel toward the four-stroke, electronically controlled Series 60.

If you’re into diesel history, engineering design, WWII machinery, classic heavy equipment, or the stories behind America’s industrial age, this is a deep dive into one of the most influential — and often overlooked — engine empires.

America’s Indestructible Engine…

Chapters
00:00 The 1938 decision that changed American diesel
00:25 Why GM created Detroit Diesel Engine Division
01:31 A new philosophy: modular, mass-producible diesel power
02:20 The breakthrough: the Series 71 modular cylinder design
03:03 Two-stroke advantage and why it mattered
03:31 The Roots blower: making high-speed two-strokes possible
03:59 Unit injectors: simple, precise, field-serviceable fueling
04:34 Wartime production surge and scale
05:16 WWII machines powered by Detroit Diesel
06:25 Battlefield serviceability: fast repairs in the field
07:59 Postwar takeover: buses, fire engines, harbors, highways
08:33 One million engines and the “Screaming Jimmy” nickname
09:09 New series: 53, 149, and 92 as demands grew
09:51 Emissions, fuel prices, and the shift to four-stroke rivals
10:09 Series 60 arrives and the ownership changes
10:30 The end of the Series 71 era and what lives on today

Thanks for watching! If you’ve ever worked on a Detroit Diesel (or heard one scream down a dock), drop your story in the comments. If you enjoyed the deep-dive engineering history, give it a like, share it with a fellow gearhead, and subscribe for more.