Duramax - Heavy Duty Engine

Where It All Started

The very first diesel engine used in Chevy trucks was a 5.7 liter Oldsmobile engine from GM capable of only 120 horsepower and 220 lb.-ft. of torque. For this reason, General Motors moved production out of house, and in the late 80s, they partnered with Detroit Diesel to create a better diesel engine for their trucks. During this time, the turbocharged 6.2 liters Detroit Diesel V8 engine was created. And after around 20 years of partnership, GM ended their relationship with Detroit Diesel engine and moved on to Isuzu.

This partnership would later come to create an entirely new class of diesel engines known as the Duramax.

Here's a glimpse of the Duramax evolution:

Duramax LB7

Since the Detroit Diesel engine was behind compared to engines found in Dodge and Ford trucks, the Duramax engine was created to fill that gap. In 200, the LB7 was released as the first-generation 6.6 liter Duramax turbo diesel engine. This engine boasted 300 horsepower and 520 lb.-ft. of torque a significant improvement from the Detroit Diesel Engine.

It also came with 4 valves for each of the 8 cylinders while featuring a high-pressure common-rail Bosch CP3 injection pump. It is also worth noting that Duramax was the first to use this injection pump.

Duramax LLY & LBZ

In 204, the Duramax LB7 was updated and later rebranded into the LLY engine. The most notable change was that Isuzu redesigned the valve covers and included a variable geometry turbocharger, slight increases in torque and horsepower, and reduced emissions.

Enhancements to this engine were later made in 2006, where improving the variable- geometry turbo added more power and efficiency. This Duramax LBZ version also came with an upgraded diesel engine with a higher fuel injection system, a durable block design, and remodeled pistons. With these improvements, the horsepower was cranked up to an impressive 360 horsepower with 650 lb.-ft of torque.

Duramax LMM & LML

After the LBZ followed the LMM in mid-2007. The main reason for the upgrades circulated around reducing emissions to comply with environmental regulations. For this reason, the LMM had new additions such as:

  • A Diesel Particulate Filter
  • A Diesel Oxidation Catalyst

The LML later came into the market in 2011 with even more regard to emissions. This heavy-duty diesel engine came with a higher pressure fuel injection which produced a stunning 397 horsepower and capable of using B20 diesel fuel. This is a fuel mixture made up of 20% biodiesel and 80% diesel. However, the LML was later replaced by the more powerful Duramax L5P in 2016.

Duramax L5P

2017 was the year Chevy and GMC were able to compete with the big boys--Cummins and Power Stroke engines. With the Duramax, L5P came improved power, efficiency, strength, and durability. Boasting a whopping 445 horsepower with 910 lb.-ft. of torque, this is surely an engine worth a look.

As if that was not enough, the LP5 Turbo engine comes with a 38% noise reduction.

Why Duramax is Here to Stay

Today Duramax diesel engines are recognized as powerful and dependable engines capable of being enhanced by bolt-on technology and internal engine modifications. Lime other diesel engines, the Duramax performs at the highest level-- with proper maintenance and attention of course.

For more information on Duramax Diesel Engines, contact us.