{"id":21044,"date":"2026-09-25T18:00:35","date_gmt":"2026-09-25T22:00:35","guid":{"rendered":"https:\/\/www.autonocion.com\/us\/?p=21044"},"modified":"2026-09-25T06:07:01","modified_gmt":"2026-09-25T10:07:01","slug":"gms-massive-new-555-horsepower-diesel-v8-is-surprisingly-tech-forward","status":"publish","type":"post","link":"https:\/\/www.autonocion.com\/us\/gms-massive-new-555-horsepower-diesel-v8-is-surprisingly-tech-forward\/","title":{"rendered":"GM’s Massive New 555 Horsepower Diesel V8 Is Surprisingly Tech-Forward"},"content":{"rendered":"

The old adage that there\u2019s \u201cno replacement for displacement\u201d isn\u2019t technically true, but it\u2019s seemingly part of the logic behind the company\u2019s massive new 8.3 liter Duramax diesel.<\/p>\n

GM\u2019s huge new engine offers more horsepower and torque than Ford\u2019s 6.7 liter Powerstroke and RAM\u2019s 6.7-liter Cummins. To be specific, that\u2019s 555 horsepower and 1,230 lb-ft of torque, compared to 500 horsepower and 1,200 lb-ft from Ford and 430 horsepower\/1075 lb-ft from RAM.<\/p>\n

Obviously, the block and internals need to be robust to handle this kind of output. GM says the block is made from \u201ccompacted graphite iron\u201d while the internals feature a fully forged crankshaft and connecting rods. There\u2019s also a variable geometry turbocharger forcing air into the thing and upping the power.<\/p>\n

The huge V8 is surprisingly tech-forward<\/h2>\n
\"A
Credit: GM<\/figcaption><\/figure>\n

While a massive diesel engine can seem a little brutish, GM\u2019s latest effort actually has a good amount of technology behind it. In thermal terms, the engine uses a dual stage air to water charge cooler to keep the temperature down. An integrated intake design, advanced combustion system and crankshaft isolation hardware are all there to reduce noise and vibration. A new aftertreatment layout targets emissions, making sure the gases coming out of the back of it are pretty clean.<\/p>\n

An Allison 10-speed 10L1000 transmission sits between the block and the wheels. The gearbox comes with \u201cadvanced shift logic\u201d which is designed to smooth out acceleration, keep the vehicle sitting in its power band, and make heavy trailers easier to handle.<\/p>\n

A lot of the tech is aimed at improving the towing experience. The cooling system means you can haul a heavy load a longer distance without issue. That journey should also be smoother and quieter.<\/p>\n

The new engine puts GM ahead of both Ford and RAM when it comes to raw power and displacement. However, despite the diesel\u2019s immense size and ridiculous amount of torque, the Ford Super Duty still edges it out when it comes to towing capacity.<\/p>\n

With a gooseneck hitch, a truck powered by the new Duramax V8 can haul a staggering 38,000 pounds. But Ford says the Super Duty can still pull up to 40,000. If you\u2019re towing conventionally, the Duramax maxes out at a still impressive 20,000 pounds.<\/p>\n

The hardware around the engine has also received a bit of an upgrade. There\u2019s new rack and pinion electric power steering, and a new electronic brake boost system built on heftier 14.6 inch rotors and four point piston calipers.<\/p>\n

The new 8.3 liter Duramax engine is being built for the Silverado 3500 HD<\/a> and Sierra 3500 HD, and it is a pretty clear statement of intent from GM. Between people who tow things commercially,<\/p>\n

There is also a gas option, if diesel prices are a worry. The Enhanced 6.6L gas V8 GM has made available in its heavy duty trucks is also best in class when it comes to torque, though the 427 lb-ft is way below what a diesel will give you.<\/p>\n","protected":false},"excerpt":{"rendered":"

The old adage that there\u2019s \u201cno replacement for displacement\u201d isn\u2019t technically true, but it\u2019s seemingly part of the logic behind … <\/p>\n

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