Information Resource for the Duramax Diesel & 2500HD/3500 Trucks
Updated April 15, 2008
The new Duramax 6600 light-truck diesel engine has launched General Motors into the lead in performance, fuel economy, reliability, and driveability. Since 2000, our own in-house on-road towing tests, comparing GM, Ford & Dodge, have proven GM's Duramax to be the most towing-capable diesel engine.
This is not a General Motors Corporation web site. The Diesel Page is a membership based web magazine providing GM light-truck diesel enthusiasts with news and information designed to improve your ownership experience. Our membership program also helps each of us share a common interest and learn from each other. TheDieselPage.com will continue to have the most comprehensive collection of GM diesel editorial found anywhere.
The Duramax 6600 light-truck diesel engine is a result of a joint venture between Isuzu and General Motors Corporation (forming DMAX Ltd.). We'll have all the latest information and test reports as that information becomes available, both for the new Duramax 6600 diesel engine and the new drivetrain (including the Allison 1000 series automatic transmission). Please scroll down this page to see what information is currently available.
While many of the articles linked here are available to the public, some are reserved for subscribers. Please support our effort here, and visit this link to see how easy and inexpensive it is to become a subscribing member. You'll have access to even more diesel news, product tests and monthly feature articles devoted to the Duramax 6600 and the new GM 2500HD/3500 trucks.
Duramax Diesel Conversions The 1989 Chevy K1500 appearing here was the very first privately owned 1988-98 C/K LB7 Duramax diesel conversion. Go here to see the truck and learn more about Duramax conversion projects.
TheDieselPage.com Forum is now available. Join us for more discussion about GM's Duramax diesel engine and powertrain.
Original Duramax Related Articles Produced by TheDieselPage.com
The Diagnostic Trouble Code P0093 applies to the 2001 model-year Duramax. This trouble code was updated for the 2002-2004 model year engines, and received a new number - P1093. Each refers to the same problem. P0093 & P1093 are defined as "Fuel System Large Leak Detected", which could mean that one or more injectors are experiencing a high fuel-return flow rate. People usually start looking beneath the truck for signs of fuel, but this isn't that kind of a leak. Let's have a look at these, and other related trouble codes, to provide a little more insight into what they mean and how to deal with them. Available to subscribers now in the Member's Area.
Product Review: For several years now, we've been hearing reports of transfer case fluid leaks due to a wear-through on the rear case half. If not caught before a leak develops, the transfer case could suffer complete failure due to a lack of lubrication. The most reliable solution includes installing an aftermarket part that prevents a case wear-through from happening. Follow along as we show you the problem and describe what it takes to produce a permanent solution.
Added January 15th Towing EGTs Does Adding Power Increase EGT?
The short answer is "not always". I had an opportunity earlier this year to perform a series of towing tests, comparing stock exhaust gas temperatures to those while using a VanAaken performance module for the LB7 Duramax. We've all seen the admonitions for installing a set of boost pressure/exhaust temperature gauges and a performance exhaust system before adding power. This has been and remains excellent advice, but more people than you know have added power while maintaining the factory exhaust system. Go here to find out what really happens. Available to subscribers now in the Member's Area.
Added December 15th Duramax Tech Broken Turbo Downpipe Bracket
I had the exhaust system off my '01 GMC recently and noticed that my truck's downpipe bracket had broken. Find out how to inexpensively repair this somewhat common problem. Available to subscribers now in the Member's Area.
Added November 15th DirtyMax Pro-Stock Duramax Diesel
Seemingly overnight, diesel drag racing has swept the nation, and is becoming more popular as each racing season passes. To help fill the need for speed, more retired Pro-Stock drag race trucks are being brought out of retirement, but not to run blown nitro burning bigblocks. Nope... The trucks are rocketing down the track with the state-of-the-art in diesel performance. Brad Makinen brought new life to a retired gas Pro-Stock truck in the form of "Dirtymax", a Duramax diesel powered Chevy 1500. This truck appeared at a drag race event I attended this past June here in Montana, which provided an opportunity to look beneath the fiberglass skin to see what it takes to make a Pro-Stock diesel run in the 8-9 second range. Available to subscribers now in the Member's Area.
Added October 15th Turbochargers For the GM 6.5 & Duramax
Learning more about turbocharger theory can help the performance-oriented Duramax owner achieve a level of cool-running and long-term performance beyond that provided by the factory turbocharger. Available now in the Member's Area.
Added August 15th Chevy -Vs- Ford Tow testing the new emissions LMM Duramax and 6.4L Powerstroke
A recent pickup truck ad I saw on television said: "Truck guys will tell you taking off with 10,000-lbs ain't no picnic. Stopping 10,000-lbs ain't no picnic either." We agree. Towing tests are few and far between in the automotive media. Most of what we see are dyno results, 1/4-mile elapsed times, and generalized reports about on-road capability. Those types of tests can provide some clue about what we might expect to see while towing a heavy trailer, but they fall short of a real towing evaluation. Part of what most potential GM & Ford buyers really want to know is how the newest diesel pickups stack up against one another in a real-world towing test on a real hill while towing a trailer that weighs at least 10,000-lbs. That's what this test was all about.
General Motors announces an all-new 4.5-liter V-8 Duramax high-output diesel engine for the Chevrolet Silverado and GMC Sierra light-duty pickup trucks and the HUMMER H2. The engine fuel efficiency offers a 25 percent advantage compared with gasoline engines. Environmental benefits of the new engine include a 13-percent reduction in CO2 versus gasoline engines, and at least a 90-percent reduction in particulates and NOx when compared to diesel vehicles today. GM-Media News Release
Added July 14th Dyno Days US Diesel Parts hosts first annual event
First events are always fun to attend, and US Diesel Parts' first annual Dyno Days, held this past June 2nd, turned out to be a well-attended and all-around fun event for just about any diesel or automotive enthusiast. The rollers on the Mustang MD-1100 dyno were spun thirty two times by a variety of diesel pickups, as well as classic and contemporary muscle cars. Diesel pickups were the big power producers, with seven of them making more than 500 horsepower, and TDP's Lil Red topped the list with 632. We also saw a brand new Ford 6.4L PSD and a new LMM Duramax diesel spin the rollers. Click the above link to learn more.
After six years and nine months of continuous production, DMAX Ltd., the maker of the Duramax 6600, celebrated producing its 1,000,000th engine on April 16, 2007. According to DMAX, they can sell all of the engines they produce and more. Go here to see the story and learn more about what makes the Duramax 6600 so successful.
The new VIN code 6 2007i LMM Duramax equipped trucks have arrived, and along with them the new DOC/DPF (Diesel Oxidation Converter/Diesel Particulate Filter). Changes in the emissions system are the big news, and this article should help to explain what's new & different and shine a light on what LMM owners need to know to have the fewest problems. Go here to see original photos of the new emissions components, and learn how these components function. Do we need to worry about the 2007 emissions systems? Available now in the Member's Area.
I recently upgraded the stock mirrors on my 2005 GMC 2500HD to the 2006 model trailer towing mirrors. Although the stock mirrors extended for trailer towing, I was not happy with the narrow field of view the stock mirrors provided. For the 2006 model year, GM released a new style extendable towing mirror, similar to the Ford SD towing mirrors. Go here for a photo-illustrated step-by-step guide to installation. Available now in the Member's Area.
Here, you'll find 43 of the top GM Technical Service Bulletins pertaining to these trucks and the Duramax/Allison drivetrain. Included are the bulletin number, the title and a summary for all 43 listed bulletins. This compilation contains great information you need to know. Available now in the Member's Area.
Going all the way back to 2000, GM has admonished technicians and vehicle owners not to allow the metal-cased ECM (Engine Control Module) and TCM (Transmission Control Module) to be used as a grounding location that could subject the electrical system to excessive electrical current. Find out what happens when this occurs. Available now in the Member's Area.
Designed to meet the 2007 emissions regulations, the 2007 LMM Duramax 6600 diesel engines have met the challenge, and continue to lead in power & torque. More power and torque are the good news. Go here to learn all of the details about the new engine and its application.
Added November 15th SEMA Trucks Go Big or Go Home!
Trucks at SEMA were there to attract attention - and boy did they! Each of the 2100+ Vendors and manufacturers who attend the annual Specialty Equipment Market Association event needed something special to lure some of the 100,000+ passers-by (and the media) into their booth. Having an eye catching truck helps them do just that, and this year was no exception. Here is a collection of GM, Ford & Dodge (and Toyota) trucks I thought stood out in some way from the others at SEMA 2006. Have a look!
Product Review: The Allison 1000-Series 5/6-speed transmissions are simply the best and most durable automatics to ever have been installed in a pickup truck. When using stock power, it's practically impossible to hurt the transmission or exceed its torque handling capability. As good as the Allison is, however, it's still possible to exceed its torque handling capability when using a power adder. Most Allisons will hang onto at least 75 additional horsepower and 200 lb-ft of torque, but living on the ragged edge can take a toll on long-term durability. This is why installing a performance-built Allison can increase the fun!
Reducing emissions components found in diesel exhaust is not without its share of engineering challenges and increased cost. While some fear for the future of the light-truck diesel market, we here at The Diesel Page remain optimistic - in fact, confident that the current trend in light-truck diesel usage will continue. Go here to find out what we'll need to know and how the new fuel and emissions requirements will affect all of us.
GM has a lot riding on the 2007 model year. With nearly 50% of all new vehicles sold in the U.S. being pickup trucks, this market is something General Motors simply has to do well in. Introduced as a 1999 model, the outgoing Silverado is now eight model years old, and has begun losing ground to the fresh faces offered by both foreign and domestic competitors. Enter the GMT-900, a new for 2007 body style that introduces a long list of refinements in addition to all new sheet metal. Included here are new photos and information about the new 1500 series trucks, and we'll discuss how the design features shown here could appear in the upcoming 2500HD/3500.
A looming grade can either induce dread or anticipation; depending on whether you're driving the highest rated diesel pickup the "big three" have to offer. Included here is an accounting of the 12 trucks that pulled the hill this year, which included 4- Duramax's, 4- Powerstrokes, 2- Dodge Cummins, and 2- 6.5TD's. Find out what truck is the King of the Hill.
After considering all the various cold air intakes systems available for my truck, I decided to develop my own, which only cost a few dollars and an hour or so to complete. Keeping the intake air as cool as possible improves power and may improve fuel economy. While inexpensive, this modification retains the excellent filtering ability of the stock air intake system.
Product review: Last month we showed you how to update the 2001-2004 LB7 Duramax ECM with one programmed for more power & better fuel economy. This month, we look at the 2004.5-2005 LLY Duramax ECM.
Added June 15th Custom Programming the LB7 Duramax ECM
More Power - Better Fuel Economy!
Product Review: The various electronic power products have done a remarkable job of increasing Duramax diesel performance, but till now, we've had to accept whatever programming or tuning options were offered by the aftermarket. The recent appearance of custom ECM (Engine Control Module) programming has increased the number of options for nearly every truck owner, whether they're looking for a few more miles per gallon, a safe towing program or a killer track tune. Kennedy Diesel is now offering custom ECM tuning, which provides for a host of additional programming features.
There are two schools of thought regarding performance product development for the diesel market. One is the shotgun approach, where you make an intuitive guess about what method or design would improve performance - first trying one approach then another, hoping to achieve a performance improvement. The second approach is where a design is taken from the theoretical to production, which achieves the performance goals set by the client. This is the realm of engineers - light truck diesel engineers in particular. I spent some time recently with the folks at BD - Diesel Performance in BC Canada, and learned more of what it takes to correctly design a range of products that really do improve performance - the right way.
In an effort to reduce cold-start induced white smoke, GM has upgraded the glow plugs, the glow plug controller and the ECM programming on a continuing basis since first introducing the first Duramax 6600 in the fall of 2000. The 2006 Duramax, identified as either RPO code LLY (early '06 models) or LBZ (late '06 models), saw another glow system upgrade. Faster-acting glow plugs and shorter cycle times combine to further reduce white smoke after a cold start, while helping to make diesel engine operation more transparent to those more familiar with starting a gas engine. However, there have been a few bumps in the road regarding the 2006 glow system.
The NEW Duramax Conversions bound volume is now available! This color laser printed 60-page bound volume contains 104 images & diagrams and descriptive text covering what you'll need to know when installing an LB7 Duramax 6600 diesel engine and Allison 1000 automatic transmission into a 1988-98 classic C/K GM pickup truck or Suburban. Click Here to see a full description of what the conversion guide includes.
The NEW Duramax 6600 1999-2004 bound volume is now available! The Duramax 6600 - 1999-2004 volume contains every important feature article, product review and tech article that appeared here in The Diesel Page from 1999 through early 2004. Written by enthusiasts for enthusiasts, this is the most comprehensive collection of Chevy/GMC Duramax 6600 and vehicle related information available to truck owners. All totaled, there are 43 articles in 189 information packed pages, and illustrated with 290 photos.
Your truck is fast, but just how fast is it? Or, maybe you've added some performance equipment, and can't really tell whether the additions (and the costs involved) made a difference. Chassis dynamometers and 1/4-mile tracks can be used to accurately measure vehicle performance, but for most of us, getting to a track or dyno can be both expensive and oh so inconvenient. That's the beauty of the G-tech. Relatively inexpensive, yet accurate, performance meters like the G-tech Pro RR featured here allow you to test and tune at any safe and convenient location and as often as you'd like. The G-Tech Pro is the latest rendition of performance meters manufactured by Telsa Electronics, Inc. Let's have a look at what the G-tech can do for you. Available now in the Member's Area.
Fuel Quality can determine whether your diesel fuel injection system provides typical service or whether you are plagued with frequent visits to the dealership. GM recently upgraded the factory fuel filter element in an effort to help protect the Bosch high-pressure common-rail fuel injection system used by the Duramax 6600. Trapping more and smaller particles in the fuel can improve both fuel quality and injection system longevity. Lubrication Specialist Greg Landuyt has developed an easy to install and cost effective auxiliary fuel filter kit that can add a significant safety margin to the diesel fuel you're using.
Product Review: As diesel fuel injection systems become more complex and more sensitive to fuel quality, owners have become more tuned-in to the nature of diesel fuel systems. Being able to check fuel pressure (vacuum) can help an owner diagnose a future problem or allow him to monitor the condition of the fuel filter in an on-going basis. This not only can save you a lot of frustration in the high-stakes game of vehicle service, but can save you money on fuel filters by not replacing them till the fuel restriction gauge tells you it's time.
Got Boost? KD Boost Valve for the 2001-2004 LB7 Duramax 6600
Product Review: There's an old saying that says "offer a great $5 part that installs in 5 minutes, and you'll sell a million of them." Well, the KD boost valve might be a little more than $5, but it is still inexpensive, installs in minutes, and offers a lot of bang for the buck. This simple device increases maximum boost pressure about ~5-8 psi, and makes the factory LB7 turbo a lot more responsive under all operating conditions. Combine this with any one of a variety of Duramax power mods, and you'll see an even bigger improvement in power than what a power mod by itself delivers.
The third annual Edge Products' "Weekend on the Edge" event was held near Salt Lake City, Utah this past September. For anyone who loves diesel engines, fast trucks and big-big power, this was a weekend you didn't want to miss. Click the above link to read more about it.
We hear of Allison fluid leaks every once in a while, and have recently experienced one ourselves. Most of these leaks result in automatic transmission fluid dripping off the bellhousing area of the transmission. An input shaft seal problem probably comes to mind first, but as we've learned, these seals are rarely the cause. Follow along we show you what to look for and how to repair a leaky Allison. Available now in the Member's Area.
The 2006 model-year Chevy & GMC diesel pickups began arriving on dealer lots in August of this year. While not much has been added or changed to the pickup styling or option list, the big news is the new RPO code LBZ Duramax 6600 diesel engine. Go here for a look at the new trucks and to learn more about the new uprated Duramax diesel engine.
Making big power these days requires help to burn all of the fuel provided by the power modules and programs used in competition, and nitrous helps burn that fuel and make more power. If you're after the most Duramax diesel performance, all roads lead to nitrous oxide.
The number of different gauges and gauge accessories has grown considerably since our 2002 gauge install piece. I recently stopped by to see the folks at USDieselParts.com, and got acquainted with what's new for those looking for gauges and gauge accessories. Let's have a look.
Measuring engine and drivetrain performance on a real hill and with a real load is in essence what a Pull-Off is all about. Each Pull-Off has two primary objectives: 1- To learn how stock diesel pickup performance evolves with each new model year, and 2- Track the performance improvements made possible by the aftermarket. The Pull-Off is simply the best way to measure the towing performance of a diesel pickup truck. What's it take for a modified truck to rule the hill? Click the above link to learn more!
TheDieselPage.com Editorial LT265/75R16
What you need to know before upsizing tires on your Chevy/GMC 2500HD
Tire size is a proportional feature that plays into how we perceive the appearance of a pickup truck. Most agree the factory tire size for the 2500HD of 245/75R16 has always appeared to be too small. Nearly all agree - except that is, for GM.
A bright yellow Service Engine Soon or Message Center warning usually means trouble. Luckily, this "Service 4WD" Message Center warning light often means you'll just need to replace the pushbutton switch panel that controls the NV-263 selectable-shift transfer case (RPO code NP1). Go here to find out how. Available now in the Member's Area.
The key ingredients to more turbodiesel power are more fuel and higher boost pressures. The Banks Big Head incorporates an adjustable turbo wastegate linkage, allowing you to raise boost pressure to get that power increase.
Performance tuning/flash programmers appear to be carving out a market with the Duramax performance crowd - and for good reason. Programmers offer a number of unique features that make them a "must have" for any Duramax owner. Here is a brief summary of five Duramax power programmers, and a list of features available for your Duramax.
Product review: Big power can stress unmodified chassis and suspension components in ways that limit overall truck performance. Pushing ¼-mile times into the 13's is relatively easy. Going faster requires more power, more effort and more attention to chassis setup. The recent installation of Kennedy Diesel's traction bar system in our Duramax Diesel hot-rod is a step toward the 11's. Available now in the Member's Area.
We're always looking forward to the mid-year announcements of the upcoming model lineup for GM's 2500HD/3500 pickup trucks. Evolutionary changes to both the exterior appearance and to mechanical/electrical systems enhance function and help improve ownership satisfaction, and the 2005 models continue that tradition. While we tend to focus on the 2500HD/3500 models, you'll find the powertrain specs for the gas engine equipped trucks here as well as those powered by the Duramax diesel.
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.
Product Review: You hold in your hands one of the most remarkable power upgrades available... So begins Edge's product description on the back of the box. After having spent some time with the new Juice/Attitude, I tend to agree. In addition to the 5-level 0-150 horsepower increase (depending on model) available at just the touch of a button, the Edge Juice with Attitude monitor combine to produce a truly comprehensive engine performance package for the Duramax diesel.
Product Review: Squeezing the last bit of performance out of a turbo diesel involves improving exhaust flow and intake airflow. Performance air intake systems are the best way to help your engine breathe, and AFE produces a line of products to help achieve maximum intake air flow. Documenting performance improvements using a chassis dyno helps answer many questions, and we thought you might be interested to learn what we discovered after installing an AFE Stage II performance air intake system on our 2001 GMC 2500HD equipped with the Duramax/Allison.
General Motors has extended the Duramax 6600 fuel injector warranty coverage for owners of all 2001 through 2004 model-year Chevrolet and GMC Duramax 6600 equipped pickup trucks. Go here to read all about it.
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.
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.
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.
Uni Foam Racing Air Filters With applications for the
6.5L & 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 virtually 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.
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 single best Suburban ever... Available now in the Member's Area.
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.
Many Duramax/Allison related articles are now available to members of The Diesel Page in the Member's Area Duramax Page.
Industry News:
August 25, 2005: GM announced a voluntary customer satisfaction program (#05546) for current owners of Duramax diesel equipped vehicles. In a letter dated August 2005, current registered owners were informed that they are eligible for one free fuel filter replacement, and GM has instructed their dealer network to perform this service free of charge through September 30, 2006. Please contact your local dealer to learn more about this free offer, or call 1-888-996-9463 if you need more information.
