This category is dedicated to the GM Duramax LLY 6.6L diesel engine in Silverado and Sierra 2500/3500 trucks. Our Duramax LLY content includes articles such as the best LLY performance upgrades and the most common engine problems. Duramax diesels are a big focus for the ChevyTrucks team, so check back for more unique, insightful LLY guides.
When the GM Duramax LLY was launched halfway through the 2004 model year, it represented a step forward in the Duramax diesel engine family. The LLY took the place of the outgoing LB7 Duramax and improved upon some of the LB7’s shortcomings. While the Duramax LLY was an unquestionable improvement over the LB7, it still…
General Motors/Chevrolet produced the Duramax LLY 6.6L diesel V8 engine from 2004–2006. Depending on the mode, it produced 210–310 horsepower and 520–605 lb-ft of torque. It was the replacement for the LB7 V8 diesel engine, and was soon succeeded by the LBZ V8 diesel engine. While at the time, its 210–310 horsepower figure was decent,…
With the capability of the stock turbocharger, the LLY Duramax left tons of power on the table. These engines are capable of pushing beyond 500rwhp with just a few bolt-on mods, and an upgraded transmission. In this guide we are going to cover the LLY’s power limits and discuss the 7 best performance upgrades to…
In order to meet stricter emissions regulations, the LLY replaced the LB7 engine and was the first Duramax to use EGR emissions technology. Unfortunately, the new EGR system was problematic leading to common valve failure. Aside from this addition the new engine received a variable vane turbo and eventually got some block and internal upgrades…
