MAN will introduce wide-ranging changes to its diesel engines, trucks, and buses and will unveil new hybrid models at the IAA Commercial Vehicle Show in Hannover this September.
The company has pursued the development of Euro 4-compliant heavy diesels using enhanced exhaust gas recirculation (EGR) to control emissions without the use of exhaust aftertreatment additives. At the IAA show, the company will focus attention on the latest developments—engines that comply with Euro 5 and the voluntary European EEV (Enhanced Environmentally Friendly Vehicles) emissions limits.
All MAN TGL light and TGM middleweight trucks and MAN and Neoplan buses will be able to comply with the EEV standard without the use of exhaust aftertreatment additives. For the TGS and TGX heavy-truck series, selective catalytic reduction (SCR) using the AdBlue urea-based additive to treat exhaust gases will be the route to EEV compliance.
To meet Euro 5 and EEV limits, MAN will use lambda-sensor-controlled EGR with exhaust recirculation rates of 30% and higher. Other strategies to meet the limits include two-stage turbocharging using indirect intercooling for the intermediate stage. MAN is introducing two-stage turbocharging on all common-rail EGR engines, except the D08 series 4.6-L, 150-hp (112-kW), four-cylinder variant, for cost reasons.
Injection pressures of up to 1800 bar (26.1 ksi) are employed in the common-rail system, and the injectors are now equipped with nine-hole nozzles. For D08 series 4.6-L and six-cylinder 6.9-L engines, the maximum charge-air pressure has been increased to 4.0 bar (58 psi).
To provide the cooling necessary to reduce the charge-air temperature enough to inhibit NOx formation, MAN uses cooled EGR. A portion of engine coolant is diverted into a secondary cooling system with a low-temperature radiator capable of reducing the coolant temperature to a few degrees above ambient temperature. This coolant is then diverted to the two charge air coolers. The system removes the need for a large charge-air pipe from the front of the truck, enabling the fitment of a larger radiator.
To ensure compliance with the Euro 5 20-mg/kW·h particulate limit, MAN will fit a maintenance-free oxidizing catalytic converter for the EGR engines. To comply with the stricter EEV limits, the MAN EGR truck engines will be fitted with the company’s PM-KAT filter, already used extensively in Euro 4-compliant EGR engines. For EEV-compliant EGR city bus engines, MAN will use a continuously regenerating particulate trap.
TGL and TGM models also gain new transmissions. For lighter-duty applications without a trailer, the six-speed ZF 6 S 800 overdrive gearbox will be specified. TGM medium-weight trucks with more powerful engines will be fitted with the nine-speed ZF 9 S 1310 overdrive gearbox. There will also be two automated transmissions: a six-speed for vehicles with engines up to 220 hp (164 kW) and a 12-speed for more powerful variants.
EBS electronically actuated brake valves will be offered on the TGL and TGM models. Electronic stability control can also be specified with EBS.
The TGL and TGM light- and medium-weight Euro 5 trucks have received a mild facelift to adopt a similar appearance to the heavy TGS and TGX models. Cab aerodynamics are said to have been improved to reduce drag and lower wind noise. Structural improvements include stronger door hinges. Inside, MAN has introduced new fabrics and trim and responded to criticisms of restricted storage space.
EGR Euro 5 engines will also be available with the heavy TGS and TGX truck ranges. Those equipped with the D20 six-cylinder, 10.6-L engine offering power outputs between 320 and 440 hp (239 and 328 kW) will be equipped with EGR technology. More powerful variants fitted with the 12.4-L D26 or 16-L V8 will use SCR emissions control.
MAN promises a low consumption semi-trailer tractor unit focusing on safety features, which will be unveiled at the IAA show. No further details have been released.
New for the show will be a Lion’s City hybrid bus fitted with a D08 EEV engine and serial hybrid system. MAN claims potential fuel consumption reductions of up to 30% for the bus compared with a diesel-powered EEV-compliant bus.
The Lion’s City bus driver workplace incorporates a number of changes aimed at improving ergonomics. Externally, the intercity Lion’s City LE bus gains the optional rear LED lamps and optional front driving lights of the Lion’s City bus.
There will be a new power rating for the vertically mounted D08 engine for city and intercity buses in 2009. It will increase to 290 hp (216 kW) from 280 hp (209 kW) and will comply with the EEV standard using enhanced EGR.