6.6L Duramax Diesel FAQ
Frequently Asked Questions About the Duramax Diesel
Who manufactures the Duramax diesel engine?
The 6.6L Duramax 6600 is architecturally an Isuzu design, while General Motors designed the electronics engine controls. GM turned to Isuzu due to their large market share in the diesel industry as well as their success in diesel engine design. GM & Isuzu produce the engines through a joint venture, "DMAX", which was contracted in December of 1998. Engines are produced in Moraine, Ohio. General Motors currently owns majority stake in the company, DMAX.
How many versions of the Duramax were produced?
A total of 5 verions of the Duramax diesel (not including the 4.5L, which has yet to see production) have been produced to date. The LB7 was introduced in 2001, and was later replaced by the LLY in 2004. The LLY was then replaced by the LBZ in late 2006. The LBZ lasted until mid-2007, when it was replaced by the LMM. The LMM is being replaced by the LML for 2011 model year trucks. All the Duramax engines are 6.6 L in displacement and share similar design characteristics. Engine changes generally occurred to meet demanding emissions requirements.
What are the benefits of a V-8 diesel?
A V-8 diesel generally produces more power throughout a broader RPM range than an inline diesel. Though inline diesels are great for building low end torque, horsepower & torque drop rapidly when they are ran beyond their limited engine speed range. V-8 diesels, such as the Duramax, have proven they can produce peak torque down low, (1,800 - 1,600 RPM & below) while maintaining impressive horsepower & torque output beyond 3,500 RPM. In a light-duty diesel truck, owners benefit from great all around performance & daily driving as well as trailer towing. The V-8 diesel (in general) is the most popular configuration used in light-duty diesel trucks.
What diesel engines did Chevrolet/GMC use before the Duramax?
Chevrolet first experimented with the 5.7 L Oldsmobile diesel engine in the 1970's. This engine proved to be an unreliable & unpopular diesel powerplant. GM's next attempt at a diesel engine was the 6.2 L, and later the 6.5 L. Neither engine gained a substantial reputation and both proved to be less reliable & less popular than their Cummins & International competitors. The Duramax, however, has proven a great competitor in the light-duty diesel market.
Using my trucks VIN number, how can I tell which version of the Duramax I have?
This is a very commonly asked question. For that reason, the following page has been created to help you identify which engine version your truck has: Duramax VIN Engine Identification