By now, most people know that GM will introduce a brand new diesel engine for its HD pickup truck line next year as a 2001 model. This engine, named the "Duramax 6600", should move the GM trucks to the head of the pack in power, performance, reliability, durability, fuel economy, and quiet operation. Here's a first look at the engine and new Allison Transmission.
First Technical Report
The new GM Duramax 6600 made its official public debut at the Texas State Fair late last month. Find out what we learned from a close-up and detailed examination of GM's new diesel. This report contains many photos, and a technical discussion on the technology used in this brand new state-of-the-art light truck diesel engine.
The New GM Diesel Trucks
GM needed a product that was more than competitive to regain market share. To help them do that, they needed a truck and diesel powertrain that took handling and performance to an entirely new level. After our "ride & drive" experience with two of their new diesel trucks, it looks like GM has done exactly that.
GM's promotional launch of the Duramax began in the summer of 1999. It was at that time that we were contacted by Chevrolet's advertising agency who asked if The Diesel Page would be interested in participating in the new truck coverage. As part of this promotional campaign, Chevrolet brought both a Chevy and a GMC Duramax/Allison equipped truck here to our Montana home base in October of 1999. We were the first automotive media to test drive the new Duramax 6600 powered trucks. Read all about the results of our performance comparison between a new Duramax and a new Ford & Dodge in a real-world test of power.
A Behind The Scenes Look
Duramax 6600 Performance
Many details of the Duramax performance comparison to Ford and Dodge didn't make it into the Pull-Off power contest article. This "behind the scenes" look puts you in the trucks as they were being driven, and discusses other aspects of the Duramax performance that only an experienced diesel truck owner would recognize. You may have thought the Duramax performance was great already, now you'll learn more about the true potential of this hi-tech diesel engine.
2001HD GM Transmissions
Allison 1000 Series
Diesel light-truck manufacturers reached the torque limits of the currently available automatic transmissions some time ago. Increasing power in the current crop of diesel engines wasn't possible unless an automatic could be built to handle More Power. Find out more about the new GM automatic, and learn how it will help the new diesel trucks reach new performance levels.
Duramax Diesel Power Tour
How do you increase public awareness of a newly designed truck and drivetrain, and demonstrate the power and durability of an entirely new diesel engine?....... Putting the show on the road is one way. Exclusive interview with the Power Tour.
This article contains over four pages of Duramax 6600 engine specifications. Material specs, journal dimensions, additional power ratings, and construction techniques are all here. Also included is a discussion about Isuzu and their contribution to the DMAX partnership. Lots of good info that you won't find anywhere else.
Duramax 6600 - Pistons, Rods & Lifters
We've learned about many innovative design features of the Duramax 6600 these past few months, which help it deliver class-leading power and durability. This time we'll examine the pistons, rods and lifters, as part of our continuing technical series explaining the advanced features of the Duramax 6600 diesel engine. Several new and unpublished photos are used to illustrate this discussion.
Issues Award to
News: Popular Science Awards selects the Duramax 6600 diesel engine, manufactured by DMAX, Ltd. as a recipient for this year's Product Achievement Award.
Installing an Electronic Brake Controller
Product review: We all spend a lot of time making our trucks run faster and pull stronger. While that aspect of towing is very important, being able to safely bring your truck and trailer to a stop is perhaps even more important. This month, we'll discuss the installation of an electronic brake controller.
The original Pull-Off in October of 1999 helped to answer many questions about the performance standing of the coming Duramax 6600. The June 2001 Diesel Day Pull-Off gave us an opportunity to re-run some of the same tests, and include a number of other trucks that would give us a better picture of the overall diesel performance spectrum. The recent appearance of the PowerPlay module by Speed Zone also gave us an opportunity to compare a "chipped" Duramax diesel truck to a chipped Powerstroke and Cummins. There were some surprises this time. Find out what we learned...
Finite Element Analysis
Finite Element Analysis allowed the Duramax 6600 cylinder block design to be optimized for a balance of strength to weight. Finite Element Analysis is a mathematical technique that is used to compute the change in shape or the displacement of a complicated object subject to external forces and internal stresses. Find out more about how the Duramax 6600 cast iron cylinder block was designed.
GM's New Medium-Duty
GM has gotten serious about trucks. Code named "GMT560", the introduction of the new medium-duty series of trucks is the next step in claiming more of the work truck market. Class leading powertrains, GVW's, ride and handling, adaptable chassis platforms, and superior work truck ethics combine to give the new medium-duties an edge in a competitive market.
DMAX - Duramax 6600 Engine Production
In March 2001, The Diesel Page became the very first "media" organization to tour the new DMAX engine facility in Moraine, Ohio, in an effort to learn more about the design and manufacture of the Duramax 6600. Please join us for a close-up and exclusive look at DMAX and some of the unique features of the Duramax 6600.
Boost & EGT Gauge Product Review & Installation
For the 2001 & 2002 GM Trucks
Product review: Aside from making your new Duramax diesel truck look cool, boost pressure and EGT (exhaust gas temperature) gauges are important tools that help you manage the powertrain and help protect your diesel engine when increasing power. Follow along as we explain how important these gauges are, and show you how to install them.
2001-02 Truck Special Features
The 2001 2500HD/3500 trucks introduce a series of special and unique features. Aside from all-new powertrains, the frames, chassis components and some exterior body components of the heavy-duties are new for the 2001 model year. This "details" article provides a close-up look at some of these unique features.
Prototypes to Production
The early Duramax/Allison prototype trucks made their way into the world of truck journalism nearly a year before the first customer took delivery. During those early tests we discovered engine quietness, powertrain performance and ride quality were all at class-leading levels. For some, these trucks seemed almost too good to be true. Now that we've had an opportunity to spend some time with a genuine production truck purchased off a local dealer's lot, we'll look at how closely the production trucks compare to the prototypes.
Duramax Fuel Filter Replacement
Replacing a diesel fuel filter is one of those maintenance procedures that all diesel owners need to know. Follow along as we show you how to replace your fuel filter.
More Power & Performance for the Duramax Diesel
Product review: Whether stoplight to stoplight or hauling huge loads up steep mountain grades, the Duramax has raised the bar for diesel pickup performance. While 300 horsepower and 520 lb-ft of torque do a great job for most people, adding another ninety horsepower and two hundred fifty lb-ft of torque turns GM's new diesel engine into real fun machine. The new BD EZ-Amp performance box does just that and more.
Extendable Towing Mirrors
Product review: For anyone who tows trailers, knowing what is behind you is nearly as important as what lies in front. Till now, improving rear vision meant all of us had to "make do" with aftermarket mirror extensions that slid over the factory mirrors. The extendable towing mirrors shown here solve that problem with a highly functional and attractive alternative. These mirrors will no doubt be a sensible investment for anyone who tows trailers or carries oversized loads in the bed of their truck.
Evolution of Power
The evolution of Duramax 6600 power these past twelve months is nothing short of incredible. Four wheel drive burnouts while launching from a dead stop at a combined weight of 24,420-lbs, then cresting a 2-mile 6% hill at an astonishing top speed. This year's Pull-Off event gave everyone a much better idea of how far diesel performance has come.
Power @ USDieselParts.com
Product review: So, you did your homework. You researched all of the diesel trucks and came to the conclusion that you wanted the quietest, most powerful, smoothest riding truck on the market. The Duramax 6600 powered trucks perform remarkably well in stock trim, but adding yet more power is just a phone call away.
Injector Cup Seals
After being deluged with bogus rumors about cylinder head failures for over two years, a lot of people have been on pins & needles waiting for the other foot to drop. Fear not, there have been no confirmed cylinder head failures that we're aware of. However, there have been cylinder heads removed and replaced for other reasons. This story is about one such reason.
The 2003 GMT560 medium-duty commercial trucks should continue the "best-in-class" customer satisfaction rating GM has enjoyed for its previous medium-duty truck models. With new cab sheet metal, new chassis, new powertrains and a host of design and safety innovations sought after by the work-truck community, these new trucks should produce both a class and market leader. Let's have a closer look at what GM considers to be its most important commercial truck initiative.
Floor & Cargo Area Protection
Product review: I once thought that complete coverage of the carpeting was necessary only when the carpet was worn out. Times change... Now, instead of stressing over the water, sand, mud and gravel that either I or someone else tracks into my truck, I decided to cover the carpeting and reduce the stress level a notch or two. Learn more about the Husky Liners.
Automotive Hinge Solutions
Door Hinge Repair
Product review: A new 2-piece door hinge design was introduced along with the 1999 Silverado/Sierra body style trucks. Instead of using replaceable pins and bushings used by the earlier truck hinges, these new hinge pin assemblies utilize a swaged-on two-piece design, installed with non-serviceable Teflon lined bushings. Once they wear out (and they surely will), you're looking at big bucks for replacement. Fortunately, Automotive Hinge Solutions offers precision-made and grease-able replacements that could outlast the truck itself.
2001 GMC SLE 2500HD
TheDieselPage.com's 2001 GMC Duramax/Allison 2500HD rolled off the dealer's lot in mid December 2000. By February 15, 2003, the truck had accumulated more than 28,000 miles and 730 hours of service. For this update, I'll discuss fuel economy, service history and performance, since being put into service.
Cylinder Group Shut-Down
Member Adam Coussons contacted us recently, saying his truck was experiencing a problem that his dealership was having a hard time diagnosing. The dealer tech indicated that fuel injectors 2-3-5-8 were disabled by the vehicle computer when the engine was misbehaving. The following information should help to explain Adam's engine running problem, as well as provide more information about the Duramax 6600 fuel injection system.
Racor 600 Series
Product review: Fuel contamination can spell disaster for a high-pressure diesel fuel injection system, and experience has shown that you can't get the fuel too clean. With reports of water, dirt and other types of fuel contamination coming in from around the country, adding a second fuel filter could be more than an option for some diesel pickup owners. To add a measure of security to the fuel system, I recently added a second fuel filter to my 2002 Duramax 6600 powered 2500HD.
GlaStepTM Running Boards
Product review: For some time now, pickup trucks have steadily made inroads in replacing the family sedan for a sizeable percentage of families - and for good reason. Besides being more versatile, pickup trucks have become a lot more comfortable and fun to drive. These running boards provide a solid truck step, plus, the color-matched paint and stylish good looks provide for a highly functional and attractive accessory for the 2001-03 2500HD/3500 series GM trucks.
Telescopic Trailer Towing Mirrors
Product review: Whether trailering through congested city streets or backing into a tight mountain campsite, towing mirrors are essential. For most of us, the best towing mirrors are of the extendable/retractable variety. This is a compromise we make that provides the utility necessary when driving without a trailer and when towing. Recently, Schefenacker entered the market with their telescopic trailer towing mirrors produced expressly for the 1999-current GM Silverado/Sierra pickups and 2000-current full-size SUV's.
Duramax Power Upgrade
Product review: The Duramax 6600 diesel has a lot of untapped potential - just waiting to be unleashed. We've finally tested the latest performance module from Diesel Services Group for the Duramax 6600 that adds more capability to an already strong running powertrain. Teaming up with Van-Aaken Developments, DSG has developed a Duramax performance module that maintains important powertrain safety features, such as transmission slip protection, while delivering a smooth boost in towing power and awesome street performance.
New for 2004
Back by popular demand! Both Chevrolet and GMC have reintroduced a 4WD 3500 series single-rear-wheel one-ton pickup truck. Go here to see GM's new pickup and learn more about its uprated capacity.
Evolution of Power
Pulling a heavy trailer up a steep grade is the truest test of diesel pickup performance. The heavy-duty diesel pickup remains the tool of choice for serious towing duty, and following the trend in diesel pickup performance is the primary focus for The Diesel Page's annual Pull-Off. This year's event marks the fourth time we've evaluated GM's frontline contender in the diesel pickup power wars, in both stock trim and when modified for more power. Are the 2003 models "down on power"? Does the 8.1L Vortec outrun the Duramax in a loaded acceleration test on a 6% grade? Find out here.
Mega Fuel Filter Kit
for the Duramax 6600
Product Review: General Motors' 6.6L Duramax turbocharged diesel engine was introduced in the 2001 model year 2500HD/3500 pickup trucks and chassis cabs. Along with the new engine came the Bosch high-pressure common-rail fuel injection system. Fuel pressures as high as 23,000-psi demand much from the high-pressure pump and solenoid-controlled fuel injectors, and the less than stellar quality and cleanliness of the available diesel fuel here in the US may present some durability and longevity challenges for these components. Supplemental fuel filtration may be required.
Air Filters for the Duramax 6600
Product Review: Today's performance air filters must excel at two vitally important and yet polar opposite functions. First, they must allow the engine to breathe without unnecessarily restricting airflow. Second, today's performance air filter is also judged by its dirt capturing ability. Truck owners in the know demand an air filter that allows an engine to perform up to its full potential yet stops nearly 100% of all harmful dust and other airborne contaminants. Creating the perfect blend of unrestricted airflow and maximum dirt stopping ability is the goal of today's performance air filter manufacturers.
Engine Coolant Facts & Critical Information
GM made the switch to the new orange-colored Texaco/Havoline Dex-Cool in the 1996 model year due to its longer service cycle, longer water pump seal life, high temperature aluminum protection, and a higher coefficient of heat transfer. Recently, a bit of a controversy has developed concerning engine and cooling system corrosion involving some GM vehicles using Dex-Cool long-life coolant. This article looks at the facts from both sides of the issue, and discusses whether we as GM diesel owners need to be concerned.
Duramax/Allison Suburban HD
The best just got better!
Chevrolet's flagship SUV just got a significant boost in power and capability. Effortless towing and the potential for 20+ miles per gallon make this arguably the best Suburban ever...
Getting acquainted with your GM diesel.
Ok, you just bought a new (or new to you) diesel truck or Suburban. You might be wondering what you need to know about diesel engines to get the fuel economy, power and reliability diesel engines are noted for. What you'll find here is essential information specific to GM diesel engines that could help eliminate some of the problems experienced by new diesel owners, and help you get more out of your "new" diesel engine.
Bilstein Shock Absorbers
For the 2500HD/3500
Product Review: Sometimes you don't know what you've been missing in your truck's ride quality till you install a new set of shocks. The factory-installed shocks had just 28,000 miles on them, and given the fact that this is a 9200-lb GVW pickup truck, I thought the original shocks were doing an OK job. Installing a new set of Bilstein shocks let me know what I was missing.
Neutral Start Back-Up Switch
The Neutral Start Back-Up switch (NSBU) relays angular position of the transmission shift selector shaft to the vehicle Transmission Control Module. The NSBU has caused a problem for some of the early Allison equipped pickups, which eventually resulted in the release of a new & improved NSBU. This short treatise should help you effectively troubleshoot an NSBU related problem, and quickly and inexpensively return the vehicle to service. A complete photo sequence showing how to replace the NSBU is included.
LLY Duramax 6600
Technology changes for 2004
Introduced in January of 2004, the RPO code LLY Duramax 6600 incorporates a number of significant technology changes. Two forces control diesel engine evolution for all engine manufacturers - Emissions compliance and market share. The technology changes introduced with the LLY address both of these forces. Creating an engine with more power and lower emissions has become more challenging, but that's exactly what the LLY delivers.