After nearly five years and $1.5 billion in development, the new heavy-duty Detroit Diesel DD15 engine was unveiled Friday at the Detroit Diesel plant in Redford, Mich. The DD15 displaces 14.8 liters, and is a 6-cylinder, in-line design.
The engine maker said it features best-in-class fuel consumption as well as power and performance.
The result of the largest investment ever made in the development of an engine by an engine manufacturer, the DD15 achieves its goals through the application of a new Amplified Common Rail System (ACRS), as well as turbo compounding technology. This engine is the first in a series of new heavy-duty engines from Detroit Diesel that eventually will cover three displacement categories: 12.8 liters, 14.8 liters and 15.6 liters.
The market launch of the DD15 in the Freightliner Cascadia will take place in the second quarter of 2008, followed by the Freightliner Century S/T and Columbia models and the Sterling Set-Back L-Line and A-Line.
The DD15 is part of the Heavy-Duty Engine Platform, which will ultimately be manufactured by Daimler Trucks in Germany, Japan and the United States.
In time, engines sharing this design will be available in all Daimler Trucks heavy-duty models around the world, including Mercedes-Benz and Mitsubishi Fuso trucks. Ultimately, this Engine Platform will replace four, distinct, engine series used today by Daimler Trucks brands globally.
The Heavy-Duty Engine Platform features 90 percent globally shared parts. Engine development and production are being managed on an international level to further facilitate efficiencies.
Designed for the rigors of North American roads, the DD15 will be offered in output and torque variants from 455 horsepower to 560 horsepower and 1,550 to 1,850 pounds-feet, including dual torque ratings for special applications. The DD15 anticipates customers' needs for fuel consumption, responsiveness, pulling power, maintenance costs, and environmental sensitivity across North America.
The DD15 will be produced at the Detroit Diesel plant in Redford, Mich., which has been completely refurbished and retooled at a cost of $275 million.
"The DD15 is a best-in-class engine that embodies what the Detroit Diesel brand is all about: performance and efficiency," said Chris Patterson, president and chief executive officer of Freightliner LLC.
"Paired with our trucks, financing, and an expansive service network, DD15 is destined to make our customers even more successful in the years to come."
With its combination of exhaust gas recirculation and a particulate filter for reduced emissions, the DD15 is tailored to North America's EPA '07 emissions regulations, and its advanced design will make it ready to take on the upcoming EPA 2010 standards with a simple downstream selective catalytic reduction (SCR) device that optimizes fuel efficiency while reducing harmful NOx emissions.
Performance and Efficiency
Powerful, responsive engines with excellent fuel efficiency, performance, quiet and smooth running characteristics are a necessity in today's industry. The Heavy-Duty Engine Platform meets these needs with its robust construction, high-grade technology with four valves per cylinder, two overhead camshafts, a uniquely efficient fuel injection system, turbo compounding technology and fully electronic engine management.
DD15 was designed to offer best-in-class torque response. Early internal and driver testing has significantly exceeded expectations. Features of the DD15 that contribute to this enhanced performance include the Amplified Common Rail System (ACRS), low-inertia dual overhead hollowed camshafts and a compact, simplified turbocharger. In fact, the DD15 exhibits up to 75 percent better torque response than the current Series 60 engine. Torque response is measured by comparing relative times required to reach peak torque levels on demand.
One of the central attributes of the new DD15 is clean and efficient fuel combustion. This is based on the first electronically controlled ACRS used in commercial vehicles.
This type of high-pressure injection system with a common rail system inherently runs quietly. ACRS is the first common rail system that controls the entire injection sequence at any operating point. Because the highest pressure is only generated in the injectors, the injection processes are extremely stable. This results in quiet, refined operation with low fuel consumption and reduced emissions.
Turbo Compounding Technology
The performance of the DD15 is due in part to the combination of a turbocharger with intercooler and turbo compounding technology. At the rated engine speed of the DD15, the turbine reaches a rotation speed of more than 40,000 rpm. Power is transferred to the gear drive, and therefore to the crankshaft, via a shaft and a hydrodynamic coupling.
This arrangement produces a uniform and smooth crankshaft rotation despite the higher torque. Additionally, fuel consumption is reduced by up to five percent compared with a similarly spec'd Series 60.
Output and Torque Variants
With a wide range of eight outputs and four torque variants, there is a version of the new DD15 to suit any heavy-duty application. The following range of horsepower and torque ratings will be available in the DD15 when series production commences:
• 455 horsepower output; 1,550 pounds-feet torque to 560 horsepower output; 1,850 pounds-feet torque
• Two dual torque ratings to optimize power and efficiency needs.
Intensive Trials
During development, the DD15 was subjected to intense trials under the most extreme conditions. More than two dozen units were endurance-tested in the United States, Germany and Japan, running for well over 100,000 operating hours - the equivalent of several million miles on the road.
A total of 20 tractor-trailer combinations are currently undergoing road trials in the United States, Germany and South Africa, and have jointly covered approximately 3.5 million miles to date. Five of the combinations operating in this fleet are intentionally overloaded, tipping the scales at 130,000 pounds, while other test trucks are solo units. The road trials are conducted in all climatic conditions, ranging from the Arctic winter to hot desert regions. Twelve more trucks are performing everyday hauling operations with customers.
Compact Design and Durability
The design of the DD15 is based on six vertically arranged in-line cylinders. With compact dimensions and a length of only 56.1 inches, the engine not only suits conventional designs but also fits in cab-over-engine trucks. For high pulling power, the DD15 has a bore of 139 mm and a stroke of 163 mm, which leaves stroke reserves for future increases in swept volume.
With a cast-iron crankcase, the DD15 is one of the most robust and durable engines on the market. The crankcase features both horizontal and vertical ribs for great rigidity, with the additional benefit of reduced noise. The total engine oil capacity is 47 quarts. The oil level can be checked using a dipstick or with an available oil level sensor linked to the motor control module. Oil consumption and blow-by losses are minimized due to the engine's rigid pistons and crankcase, thereby lowering costs and improving environmental compatibility.
The crankcase has a carefully machined surface. In conjunction with the cylinder head gasket, it ensures a smooth and therefore "tight" connecting interface with the cylinder head. The cast-iron single cylinder head is connected to the crankcase with a total of 38 bolts, further ensuring rigidity and stability.
As seen in the direction of travel, the turbocharger, turbo compounding unit, starter and the crankcase ventilation are integrated into the crankcase and are arranged on the right side of the engine. Grouped on the left for ease of maintenance are the motor control module (MCM), oil cooler, a module with
