Future Of Diesel Engines - Diesel Basics
John J. DeCotis has worked in the automotive industry for 35 years. He began his career working on diesel-powered military vehicles (Detroit Diesel 8V71) and went on to Ford Motor Company to work on various chassis and powertrain programs. The latter parts of his 30 years at Ford were in truck engineering. He was involved in some diesel application studies back in the Eighties on lighter vehicles and briefly worked on the Super Duty program. He was also a member of the team that engineered a diesel-powered Ranger for South America in the late-'90s. He has no affiliation with any automotive manufacturer at this time and is an independent consultant for Diesel Power magazine.
Industry analysts have stated the number of diesel engines used in vehicles is growing twice as fast as overall vehicle growth. We are seeing statements in the media from all of the major automotive companies that they're either committing to building more vehicles with diesel engines or are finalizing feasibility to do so.
The spectrum of new diesel applications seems to be covering all types and sizes of vehicles. We have seen concepts of diesel-powered sporty cars, such as the Ford Reflex hybrid. DaimlerChrysler has made a commitment to apply its new Bluetec (clean diesel) technology to all of its vehicle brands, including Jeep and Chrysler. The Jeep Liberty (the only diesel-powered compact SUV on the market) is literally outselling volume expectations. And the traditional diesel applications (3/4- and 1-ton heavy duty pickups and SUVs) club is also going to get more members!
Interest in diesels here in the United States has been resurrected-some of us remember the last time in the late-'70s/early '80s-by the continual climb and instability of fuel prices. But, the need to conserve fuel has been growing for several years. Diesels with their inherent efficiency are making justification for the added purchase cost for a diesel easier. And diesels are a viable alternative to gasoline hybrids with fuel-saving potential in all operating modes, while the gas hybrid's strength is in city driving.
The stumbling block preventing manufacturers from offering diesels on lighter vehicles has been meeting present and future emission requirements. The mandated low-sulfur diesel fuel that will become available this year is a key element to meeting stricter emissions requirements. When used with sophisticated engine control systems, oxidizing catalytic converters, particulate filters, and urea injection to reduce nitrogen oxides, diesel engines will become viable options for every vehicle on the road.
This article is going to take a look at where the market is headed and what the future looks like for diesel-powered vehicles in the U.S. The focus will be on American trucks and SUVs. All projections are based on available data from published reports or speculations by the writer. No information has been provided or solicited from vehicle or engine manufacturers. (Basically, while extensive research has been conducted for accuracy, we can't be absolutely certain of the accuracy of facts or implementations/timing stated in this article. Hey, we're trying to predict the future, here! - Editor)
I. DaimlerChryslerDaimlerChrysler is clearly the most aggressive manufacturer in the application of diesel engines for the U.S. market. It introduced the Jeep Liberty diesel for the '05 model year, with sales exceeding expectations. The Bluetec technology introduced at the Detroit Auto Show demonstrated its future direction for clean-diesel technology.
'06-'07 Model Year ApplicationsDodge Ram 2500/3500-5.9L I-6 Cummins Dodge Cummins diesels have been in the market place for high gross vehicle weight rating (GVWR) pickup trucks since 1988. The latest version has 610 lb-ft of torque at 1,600 rpm and 325 hp at 2,900 rpm. No rating changes are rumored at this time.
Jeep Liberty-2.8L I-4 VM MotoriDiesel power for the Liberty SUV was introduced in 2005, with sales exceeding expectations. The '06 versions are rated at 295 lb-ft of torque at 1,800 rpm and 160 hp at 3,800 rpm. Fuel economy is EPA-rated at 21 mpg in the city and 26 mpg on the highway.
The Jeep Grand Cherokee with a Bluetec 3.0L Mercedes-Benz V-6 was shown at the Detroit Auto Show in January 2006. The timing was not provided, but the vehicle appeared to be production ready. The vehicle launch could be as early as the '07 model year and certainly by 2008. Expect to see the same powertrain in the Jeep Commander when launched in the Grand Cherokee.
Future ProjectionsRam 1500The Ram pickup could get a diesel engine as early as the '08 model year. DaimlerChrysler's history at innovation and aggressive implementation of diesels supports this assumption. There's no information as to engine source, but it has been rumored Cummins has been working on a new V-6/V-8 engine family. Use of the Mercedes-Benz Bluetec four-valve DOHC V-6 might be possible, but not probable, in this vehicle class due to the engine's cost.
Dodge Dakota, Durango/Chrysler AspenA diesel in this vehicle family is again probable by the end of the decade ('09 model year). The 2.8L VM Motori engine from Liberty would be a stretch, but a 3.0L-3.5L engine would better meet performance needs due to vehicle mass. Application of the Mercedes-Benz Bluetec V-6 (3.0L-3.5L) could be possible, but profitability with an expensive powertrain could be an issue.
Jeep Gladiator Compact Pickup (Concept)The concept shown in January 2005 included a 2.8L diesel (same as Liberty). This would be a very viable combination and, again, innovative in this vehicle class. Expect to see Gladiator with a diesel when, and if, it goes into production in the '09 model year.
Jeep WranglerApplication of the Liberty 2.8L diesel would make a great combination with enhanced off-road capability from the diesel torque. This could be another innovative application and continuation of DaimlerChrysler's aggressive position on diesels. It could happen by the '07-'08 model year.
II. General MotorsGeneral Motors has a 75-year history of diesel engine applications and continues to be a worldwide producer of diesel-powered products. It has stated SUVs and light trucks will be its primary focus for GM diesel technology advancements and is committed to be competitive in vehicle segments with significant consumer demand.
'06-'07 Model Year ApplicationsSilverado/Sierra 2500/3500-6.6LV-8 Duramax dieselThe Silverado/Sierra have had diesel engines since the Eighties and Duramax since the '01 model year. Power ratings for 2006 are 650 lb-ft of torque at 1,600 rpm and 360 hp at 3,000 rpm. The ratings were increased in the '05 model year, and no further increases have been indicated for the coming model year.
Future ProjectionsSilverado/Sierra 1500GM is working on a Duramax 4.9L V-6 for Silverado/Sierra 1500 (reference Diesel Power, Jan. '06). Introduction of this engine could be timed with the redesigned GMT900 pickup launch in late 2006/early 2007. Engineering efficiencies would be realized by integrating the diesel application for packaging, noise, vibration, and harshness (NVH) tuning, and powertrain calibrations purposes with the base program. Application of this engine to the Tahoe/Yukon and H2 would be feasible and probably planned following the pickup launch. Diesel engines would enhance the success of the GMT900 platform by providing improved performance and fuel economy as increasing fuel prices threaten sales in this segment. Application of the 4.9L to the Cadillac derivatives would be feasible, but probably not probable, due to NVH issues from engine configuration (90-degree V-6). Cadillac levels of powertrain smoothness may not be achievable even with a balance shaft and offset crankpins for even firing.
Colorado/Canyon and TrailBlazer/EnvoyThere has been no information published or rumors circulated indicating that there are firm plans for diesel powertrains in these vehicles.
Diesels in this class of vehicles could provide value from improved fuel economy with comparable performance to base gasoline engines.
The ideal engine size would be about 3.0L. The trucks could probably tolerate a 2.8L I-4, but NVH and performance would be an issue with the SUVs.
Outside the USAChevrolet's S-10 and Blazer vehicles in South America use a 2.8L I-4 MWM diesel engine. But, use of this engine in North America could be difficult with availability, pricing, certification, adaptability to automatic transmission (manual transmissions are optional in South American versions), and NVH, which are just some of the concerns.
Despite no identifiable engine at this time, diesels in this segment are still expected by the end of the decade ('10 model year).
III. Ford Motor CompanyFord has been aggressive in worldwide diesel applications, recently developing powertrains with PSA diesel engines for use in European Jaguar and Land Rover vehicles. Ford has not been as vocal as DaimlerChrysler with expansion of North American diesel applications, but it has been reported Ford has a dedicated team to apply diesels to cars and trucks. Ford has made no major diesel vehicle announcements, but has shown several concept vehicles with diesel and, or, diesel hybrid power.
'06-'07 Model Year ApplicationsSuper Duty: F-250/F-350-Power Stroke 6.0L V-8The 6.0L engine was introduced in the '03 model year and continues to be the highest volume diesel engine application in the industry. Power ratings are 570 lb-ft of torque at 2,000 rpm and 325 hp at 3,300 rpm. No power rating changes have been reported for the '06-'07 model year. Speculation about a twin-turbo Power Stroke seems possible-though expensive-since Navistar offers this technology on the V-6 version of the engine.
Future ProjectionsF-150 and Expedition/NavigatorNo specific information has been published about diesel applications for the F-150 and Expedition platform. Application of the Navistar 4.5L V-6 Power Stroke originally slated for these vehicles has been abandoned. The 4.5L is being used for International military applications and the LCF commercial vehicle which is a tilt-cab truck resulting from a "Blue Diamond" joint venture between Ford and International.
A six- or eight-cylinder engine of 4.5- to 5.0L would be required, but final powerplant size/configuration is open at this time, as well as engine source.
Despite the uncertainty, it is expected there will be a diesel when the F-150 is restyled for the '09 model year.
Consistent with the '04 program, a redesigned Expedition is expected to lead the F-150 by a model year in 2008, including a longer wheelbase "Expedition Max" version. It is not anticipated a diesel will be part of this program, but Expedition could receive the F-150 diesel within its cycle probably after the truck launch.
Depending on the engine configuration, the Lincoln Mark LT and Navigator could include a diesel by the end of the decade. A 90-degree V-6 would present a challenge in achieving NVH requirements, however.
Ranger and Explorer/MountaineerNo information has been published indicating either of these platforms are slated for diesel application. For different reasons and vehicle objectives, both products would be attractive for diesel engine applications. A diesel powertrain in the Explorer could help restore the segment which has suffered severe contraction due to fuel price increases and the growing crossover utility vehicle (CUV) segment.
Outside the USAInternationally, diesel-powered SUVs are attractive vehicles with the benefits of the diesel torque and the inherent fuel efficiency. Development costs for a diesel-powered Explorer would need to share with Ranger to make it viable. Ranger has been reported to be redesigned around the '10-'11 model-year time. It could be speculated that both vehicles would be subjected to a redesign at the time, and it is possible the diesel package could be communized between the two vehicles.
To help clarify confusion that there are two Ford Ranger pickups sold outside of North America at the present time: In South America, the Ranger is similar to the North American Ranger in architecture, but with locally sourced diesel engines (2.8-/3.0L I-4). The Ranger in Europe, Australia, and many other countries is derived from a Mazda-based platform and uses a Mazda-sourced 2.8L diesel engine.
Issues would exist to apply either of these engines into the present North American products but either one could be a possibility by the end of the decade.