|Predecessor||General Motors Detroit Diesel-Allison Division|
|Products||Heavy-duty diesel engines|
|Owner||Daimler Truck AG (as of 2000)|
Number of employees
|Parent||Daimler Truck North America|
Detroit Diesel Corporation (DDC) is an American diesel engine manufacturer headquartered in Detroit, Michigan. It is a subsidiary of Daimler Truck North America, which is itself a wholly owned subsidiary of the multinational Daimler Truck AG. The company manufactures heavy-duty engines and chassis components for the on-highway and vocational commercial truck markets. Detroit Diesel has built more than 5 million engines since 1938, more than 1 million of which are still in operation worldwide. Detroit Diesel's product line includes engines, axles, transmissions, and a Virtual Technician service.
Detroit engines, transmissions, and axles are used in several models of truck manufactured by Daimler Truck North America.
Detroit Diesel consists of manufacturing operations of axles, transmissions and diesel engines for on-highway only, which is owned by Daimler Truck AG. The former off-highway division was sold to MTU Friedrichshafen in 2006 and subsequently purchased by Rolls-Royce in 2014.
|Model designator||Number of cylinders||Application designation||Basic engine arrangement and drive shaft rotation or Displacement[a]||Design variation or Engine Control[a]||Specific model number or customer configuration|
|1 = Series 71, inline arrangement||2 = Marine||1 = LA (left hand rotation,[b] exhaust & balance shaft to the left,[c] or starter on left bank[d])||0 = 4 valve head "N" engine|
|5 = Series 53, inline or vee arrangement||3 = Industrial F-F[e]||2 = LB (left hand rotation,[b] exhaust & balance shaft to the right,[c] starter on right bank[d])||1 = 2 valve head|
|6 = Series 60||4 = Power Base||3 = LC (left hand rotation,[b] exhaust & balance shaft to the left,[c] starter on right bank[d])||2 = 4 valve head "E" engine|
|7 = Series 71, vee arrangement||5 = Generator||4 = LD (left hand rotation,[b] exhaust & balance shaft to the right,[c] starter on left bank[d])||3 = Turbocharged|
|8 = Series 92, vee arrangement||7 = Vehicle F-F[e]||5 = RA (right hand rotation,[b] exhaust & balance shaft to the left,[c] starter on right bank[d])||4 = Aftercooled|
|9 = Series 149||8 = Vehicle F-F[e]||6 = RB (right hand rotation,[b] exhaust & balance shaft to the right,[c] starter on right bank[d])||5 = Customer special engine|
|T = Series 4000||7 = RC (right hand rotation,[b] exhaust & balance shaft to the left,[c] starter on right bank[d])||6 = Constant horsepower, economy (TAE, California Certified)|
|8 = RD (right hand rotation,[b] exhaust & balance shaft to the right,[c] starter on left bank[d])||7 = Constant horsepower (TT)|
|8 = Constant horsepower (TTA, California & Federal Certified)|
|9 = Constant horsepower, economy (TTAE, California & Federal Certified)|
In 1998, the EPA announced fines totaling $83.4 million against Detroit Diesel and six other diesel engine manufacturers, the largest fine to date, which evaded testing by shutting down emissions controls during highway driving while appearing to comply with lab testing. The manufacturers also agreed to spend more than $1 billion to correct the problem. The trucks used engine ECU software to engage pollution controls during the 20-minute lab tests to verify compliance with the Clean Air Act, but then disable the emissions controls during normal highway cruising, emitting up to three times the maximum allowed NOx pollution.
In 2016, Detroit Diesel agreed to pay US$28.5 million to resolve violations of the US federal Clean Air Act. The company sold 7,786 heavy-duty diesel engines, which were assembled approximately 80% complete in 2009, including the crankshaft, block, pistons, and connecting rods, the short block engines were stored temporarily and completed the remaining assembly in early 2010 for use in trucks and buses of in model year 2010. These engines were alleged not to comply with stricter 2010 emission standards.