The history of the DURAMAX diesel
Back in 1996 General Motors was finalizing plans for the next generation of full-size trucks, code named GMT800, and at that time, GM had only 3% market-share for the Diesel Powered HD pick-up truck segment. In order to have a winning truck, GM had to have a winning Diesel powertrain.
At the same time, a small group of stakeholders led by the Planning Group, reviewed proposals from all the possible Diesel engine manufactures for the all new truck. The decision was reached to go with a proposal from one of GM’s partners – ISUZU Motors LTD, recognized worldwide as a leader in Diesel engines. The proposal had been developed as a part of a strategic 90-day study conducted by ISUZU and GM, relative to ISUZU’s role in the GM Global enterprise.
The problem was ISUZU’s plan called for a “Clean Sheet” brand new engine design that would not be ready until 2003 and GM’s new HD pickup truck was going into production in late 2000. GM’s chairman, Jack Smith, met with ISUZU’s chairman Kazuhira Seki in early 1997 and Mr. Seki agreed that ISUZU would find a way to pull ahead the timing to meet GM’s needs. In May 1997, the project team was established under the leadership of Jim Hogan, GM Truck Group, Yoshihiro Tadaki, ISUZU, and myself Jim Kerekes, representing GM Powertrain. The first meeting was held in Pontiac, MI with subsequent meetings being held every 6-8 weeks, alternating between the U.S. and Japan.
The project was code named “B908” (Bridge between U.S. and ISUZU, 90-day study, and 8-cylinders). This would be the first V8 Diesel engine ISUZU ever designed for the U.S. HD pick-up market. ISUZU was responsible for the base engine design and GM was responsible for the integration of the engine into the vehicle.
Due to the aggressive timetable, ISUZU needed assistance with engine development testing and calibration. The GM Powertrain – Romulus Engineering Lab became the center of activity in the U.S. and several of the ISUZU engineers were co-located there.
The first running B908 engines were available in early 1998 in Japan and soon were installed in mule vehicles in the U.S. to begin the final development. The two engineering teams worked very closely together even with the 13 hour time difference. Countless hours were spent on video conferences between the U.S. and Japan. The B908 Team used the 13-hour difference to our advantage. We would have a video conference late in the day U.S. time and review issues and problems with the Japan team. They would work on the issue during their day (our night) and when the U.S. team came in the next morning, we would have another video conference to review the progress, truly 24/7 development.
The ISUZU and GM Engineers soon got to know and learn from each other. The many “face to face” co-ordination meetings that were held became excellent opportunities to exchange cultural experiences. When the meetings were in the U.S. we would try to include an after-work activity, like a softball game or bowling, to give our Japanese colleagues a chance to learn about the U.S. culture. And when the meetings were held in Japan, the U.S. engineers also had the opportunity to experience the Japanese culture. We will never forget the unique dining experiences – sitting on the floor, eating raw fish or the opportunities to express our vocal talents at the Karaoke bars…”I get by with a little help from my friends!” -The Beatles. A few of us had the very special honor of being invited into the Japanese home of one of the ISUZU engineers for a very personal experience of Japanese lifestyle, for example, the eating of uncooked beef dipped in raw egg. (You can only imagine the expression on my wife, Susan’s face!) And after 40 some trips to Japan, I have personally come to respect and honor the Japanese culture and their values of hard work, determination and politeness.
The GM-ISUZU 90-day study established the plan to manufacture the new engine; a joint venture company, 60% owned by ISUZU and 40% by GM. The company was established in September 1998, in Moraine, Ohio. A new 650,000 square foot engine plant was built near the former 6.5 L Diesel Engine plant, and many of the employees were able to transfer to the new joint venture named, DMAX Ltd., signifying the Diesel engine and maximum power, cleanliness and fuel economy.
The totally new engine design was a 6.6L, 90 degree, direct-injection, overhead valve, four-valve-per-cylinder turbocharged Diesel V8 with aluminum high swirl cylinder heads. The electrically controlled common-rail fuel system provided maximum power for each pulse of fuel used and allowed full authority in injection timing and quantity. This combination along with pilot injection resulted in Best-in-Class operating quietness and smoothness typical with similar sized gasoline engines.
The new engine was targeted to meet Best-in-Class-Performance for power and torque. In order to transfer the 300 hp and 520 ft. lbs. of torque to the truck’s wheels, a new 5-speed automatic transmission was developed. The Allison Transmission 1000 series was chosen to complete the winning Powertrain. The B908 Team worked very closely with Allison Transmission Engineering Team to match the performance characteristics of the engine with the transmission.
Then it was time to decide upon the marketing name for the new B908 engine. The previous attempts to introduce Diesel technology in the U.S. by GM had not been very well received by the customer. The name itself was critical as it would compete against Ford’s established “Powerstroke” Diesel engine. So after many meetings and discussions with Chevrolet Truck and GMC’s marketing, the name: Duramax Diesel 6600 was agreed upon. “Duramax” was meant to highlight the durability and reliability of the new engine.
In late 2000 the Duramax Diesel 6600 debuted for the new 2001HD pick-up trucks in only 37 months as the fastest new engine developed by GM Powertrain -at that time. The engine was an immediate success bringing up GM’s market share from 3 percent to 30 percent in the HD Diesel pick-up truck market.
Ward’s Magazine “10 Best Engines in the World” Award Presentation to the Duramax Diesel 6600 Team in 2001 at the GM Powertrain HQ
The Duramax Diesel 6600 was chosen by Ward’s Magazine as one of the “10 Best Engines in the World”, two years in a row for 2001 and 2002. It was also chosen by Popular Science Magazine to receive the “Best of What’s New” Award in 2000.
Dan McCosh, Popular Science Magazine presenting the “Best of What’s New for 2000” Award to Jim Kerekes, Chief Engineer Diesel Engines GMPT and Shinichi Ohoka, VP ISUZU Motors America
The Duramax/Allison Powertrain contributed to the 2001 Chevrolet Silverado HD Pick-up Truck being awarded the prestigious honor of the Motor Trend Magazine 2001 Truck of the Year” Award at the Detroit Auto Show (NAIAS).
Part of the success of the Duramax Diesel 6600 was due to the GM Team of employees that worked many long hours and made personal family sacrifice. This extreme Team effort was recognized by receiving a GM “Best of the Best” Chairman’s Honors Award in 2000.
The Duramax Diesel 6600 V8 in the GMC Topkick appeared in the Transformers movie in 2007.
The Duramax Diesel 6600 has continued to evolve and improve, meeting the ever tightening U.S. emission standards, and leading in the extremely competitive power and torque race. Over one million Duramax Diesel 6600’s have been produced for the strong customer base. The Duramax Diesel 6600 owner’s have created several websites, blogs, and chat rooms on the Internet to discuss the great performance, fuel economy and quietness of the engine. A Duramax Diesel 6600 powered one of heroic Autobot’s, “Ironhide” in the 2007 movie Transformers. And recently, MTV’s Pimp my Ride featured a Duramax Diesel 6600 being installed in a 1965 Chevrolet Impala that demonstrated both performance and fuel economy can be achieved together using modern Diesel technology.
The Duramax Diesel 6600 helped change the perception of Diesel engine technology for GM in North America. The success of the Duramax Diesel brand-name is now being extended onto other GM Diesel products for Chevrolet and GMC.
The history of the POWERSTROKE diesel
In mid 1994, the 7.3L Power Stroke diesel was introduced. Although the previous 7.3L had the same displacement, there weren't any other similarities between the two. The Power Stroke is an electronically controlled, direct injection engine with a 4.11 in (104.4 mm) bore and 4.18 in (106.2 mm) stroke creating a displacement of 444 cu in (7.3 L). It has a 17.5:1 compression ratio, and has a dry weight of approximately 920 lbs. This engine produced up to 250 hp (190 kW) and 525 lb·ft (712 N·m) of torque in automatic trucks during the last years of production, and 275 hp (205 kW) and 550 lb·ft (746 N·m) of torque in manual trucks. The 1994.5 to 1996/97 DI Power stroke had "single shot" HEUI (hydraulically actuated electronic unit injection) fuel injectors and ran a 15° high pressure oil pump (HPOP) to create the necessary oil pressure to fire the fuel injectors. 1994.5-1997 trucks used a cam driven fuel pump, whereas the 1999-2003 trucks used a frame rail mounted electric fuel pump. The California trucks in 1996 and 1997 had split shot fuel injectors whereas the rest of the trucks didn't get split shots until 1999. The difference between the split shot and single shot are the single shot only injects one charge of fuel per cycle, whereas the split shot releases a pre light load before the main charge to initiate combustion in a more damped manner. This controlled injection helps reduce the sharp combustion 'knock'. It utilizes a single turbocharger with a turbine housing size of 1.15 A/R. In 1999, an air to air intercooler was added to cool the charged air from the turbo making it more dense. The cooler, denser air would increase the horsepower potential of the engine, while also reducing exhaust gas temperatures (EGTs). Eventually, the turbine housing was changed to a .84 A/R housing and a wastegate was added. With larger injectors, the HPOP was advanced to 17° to change fueling characteristics. The 7.3 L DI Power Stroke was in production until the middle of model year 2003 when it was replaced by the 6.0L.