Attention: If you have a GM Duramax, please verify your engine type before ordering any product. Many of the products we offer are not interchangeable with all Duramax engine types. To Verify: Check the 8th digit in the VIN number.
VIN Code 1 - LB7 (2001-2004)
VIN Code 2 - LLY (2004.5-2006)
VIN Code D - LBZ (2006-2007)
VIN Code 6 - LMM (2007.5-2010)
VIN Code 8 - LML (2011-2016)
In 2011 the 6.6L Duramax LML was introduced for GM Silverado and Sierra 2500HD/3500HD pickups. This generation Duramax engine received some new elements to improve performance and reliability. The engine block casting was revised for better lubrication and the engine internals were reinforced to withstand the additional horsepower and torque. The common-rail fuel system was redesigned with a new injection pump and high-pressure fuel injectors. Besides all the changes to the Duramax engine, the GM trucks also received some styling upgrades. In 2011 the GM Silverado/Sierra 2500HD/3500HD pickups received new front bumpers, grilles, suspension components, and a fully boxed steel frame. In 2015 these trucks were redesigned again for a more modern appearance.
While many new components were added to the Duramax engine, some features were carried over from previous generations. GM continued to utilize the durable foundation of a cast-iron block fitted with cast-aluminum heads for the Duramax LML engine. The cast-aluminum pistons in the LML were similar to previous generations but didn’t include wrist pin bushings due to them being a failure point in prior engines. The connecting rods were still constructed with forged steel but were built to provide a lighter rotating assembly in the LML Duramax. A higher output oil pump was added to this engine to provide better lubrication with the increased horsepower and torque. Major changes were made to the common-rail fuel system for the LML Duramax. The CP3 injection pump was replaced by the Bosch CP4.2 pump that was capable of producing 30,000 PSI of rail pressure. Paired with the new pump were high-pressure Bosch piezo-electric fuel injectors that offered better atomization for improved fuel efficiency. Fitted to the LML Duramax was the Garrett GT3788VA variable-vane turbocharger which had been fitted to the previous generations, but it was modified for the LML Duramax engine. An exhaust brake was added to this turbo to act as a braking aid when hauling heavy loads. The combination of all these new components provided the LML Duramax with a significant increase in horsepower and torque over its predecessor. In 2011 a stock 6.6L Duramax LML was rated at 397 hp and 765 lb-ft of torque, which was over 30 hp and 100 lb-ft of torque over the previous generation. The Allison 1000 6-speed automatic transmission was still coupled with the Duramax engines to handle the increased torque output.
Improving horsepower and torque was one of the major focuses of improving the Duramax engine. The Duramax LML had the longest production run of any Duramax to date, lasting 6 model years until it was replaced by a new Duramax engine in 2017. XDP continues to support the GM 6.6L Duramax LML powered trucks with parts and accessories from hundreds of the top manufactures. Prevent fuel system failure on your LML Duramax with Fuel Lift Pumps or CP3 Injection Pump Conversion Kits. Significantly boost performance in your GM Silverado/Sierra 2500HD/3500HD with Turbo Upgrades, Performance Injectors, and much more all available at XDP. XDP also carries a wide range of stock replacement parts to maintain factory performance and function. XDP is your one-stop-shop for everything your 2011-2016 GM 6.6L Duramax LML needs.