Mercedes medium truck diesels set for the US

According to well-placed sources, Mercedes-Benz is planning to build medium-duty truck diesel engines in the US from 2018, given sufficient take-up of the new engines in the US and Canada.

The new engines, dubbed DD5 and DD8, could be manufactured at the Detroit Diesel plant in Detroit, Michigan if there is demand to justify the investment.

At present the engines are made in Germany at the Mercedes-Benz plant in Mannheim where the power units are known by their Mercedes nomenclature of OM934LA and OM936LA. These engines will be exported to the US for fitment into a variety of Daimler group vehicles.

Senior officials at Daimler Trucks North America LLC (DTNA) plan to make the 5.1- and 7.7-litre, four- and six-cylinder diesel engines, available in Freightliner Business Class M2 commercial vehicles from 2016, as well as other products, including Freightliner Custom Chassis vehicles, Western Star Trucks, Thomas Built Buses.

It is understood that all Daimler Trucks and Thomas Built Buses will be offered DD5 and DD8 engines, with Detroit Diesel supporting the engines through a nationwide parts and distribution network, including over 800 authorised service centres in North America. Detroit Diesel Corporation is an arm of DTNA.

Detroit Diesel makes a ‘complete line’ of heavy-duty diesel engines and axles for the commercial transportation industry. The addition of medium-duty engines would add a new line for the 2,300 or so employees.

The Business Class Freightliner trucks will continue to be available with Cummins 6.7-litre and 8.9-litre ISB and ISL diesel engines, though every effort will be made no doubt – through financial inducements – to ‘push’ the in-house DD5 and DD8 engines in the direction of customers.

The move is seen as part of Daimler’s ‘Global Excellence Strategy’ which aims to establish uniform production processes and standards worldwide.

“Detroit medium-duty engines will provide what no other manufacturer in North America can offer,” claims Martin Daum, president and chief executive officer of DTNA. “Namely, a total vehicle solution that matches Daimler’s global engineering prowess with the most complete product line-up bar none in the industry.”

According to DTNA, the entire product line, including vehicles powered by the new DD5 and DD8 engines, will meet GHG17 standards early.  

It remains to be seen, however, how North American truckers, not to mention bus operators, respond to the swept volumes of the ‘newcomers, as they are significantly smaller than their Cummins counterparts in the Freightliner M2 vehicles, for example. At present, no figures for power torque ratings and weights have been given for DD5 and DD8. Insiders note that “spec information” will be issued closer to the launch date, for which as yet “no specific date had been disclosed”. The specs will be awaited with interest all round. However, in the meantime, in Europe, the 5.1-litre OM934LA engines fitted to Atego trucks develop between 115kW (156bhp) and 170kW (231bhp), and between 650Nm and 900Nm torque. The 7.7-litre OM936LA on the other hand, likewise also available in Atego trucks, develops between 175kW (238bhp) and 220kW (299bhp), abetween 1,000Nm and 1,200Nm torque.

Detroit Diesel Corporation is one of the few diesel engine makers to have introduced turbo-compounding in its product line - both Scania and Volve have had a brief flirtation with turbo-compounding. The DD15TC develops between 455bhp and 505bhp output, and between 1,550Nm and 1,750Nm torque; the larger DD16 gives between 475bhp and 600bhp output, and between 1,850Nm and 2,050Nm torque.  

Detroit Diesel began life in 1938 when General Motors formed the GM Diesel Division. Later, on 1 January 1988,  it became a joint venture of General Motors and Penske Corporation. The arrival of Penske, then owning 60 per cent, introduced a new and more dynamic form of management. However, in 2000, DaimlerChrysler, as it was then, acquired the business, including the 48.6 per cent owned by Penske Corporation.

The company’s heavy-duty engines include the DD13, DD15, DD15TC and the DD16 - all use Bosch fuelling systems which contribute to the engines' notably good fuel economy. In 2012, the company built its 100,000^th DD platform engine. In 2013, the company manufactured approximately 50,000 engines - almost 1,000 a week.

                                           Electonic unit injectors

Diesel Technology Corporartion, a division of Detroit Diesel specialising in the design and manufacture of electronic unit injectors (EUIs), was reformed in 1997 as Detroit Diesel Remanufacturing North in Kentwood, Michigan, primarily to focus on the remanufacture of EUIs. In 2008, the business became North America Fuel Systems Remanufacturing. It is a 50/50 joint venture with Bosch LLC and remanufactures unit pumps, common rail systems, high pressure injector pumps as well as EUIs.

Other divisions of Detroit Reman include Detroit Reman East in Byesville, Ohio, for two-stroke engine long blocks and Series 60/50 engines; Detroit Reman Central in Emporia, Kansas for two-stroke new engines and Sprinte 612 and 647 engines; Detroit Reman West in Toole, Utah for miscellaneous products including turbochargers and connecting rods; and DMR Electronics in Hibbing, Minnesota for industrial electronic products, including Allison components. 

In 2005 the company opened Detroit Reman Mexicana in Toluca, Mexico in "response to growing market demand for remanufactured products". This unit handles Mercedes-Benz water pumps, cyclinder heads, manual transmissions and MBE 900 engines.