Detroit / General Motors / GM Diesel

Series 53, 72 and 92 Engine Specifications

The older Denning Mono and Austral Tourmaster coaches are powered by a variety of General Motors (GM) diesels, generally referred to as “Detroit” diesels. The series identifier gives an idea as to the age and size of the motor — most early-to-mid 1980’s coaches seem to be fitted with a series 71; series 92 a bit later; series 53 earlier. So to compare the specifications of Australs and Dennings we wanted to know something about the various Series 53, 71 and 92 diesels. The tables below are incomplete, and include industrial versions, but provide a good starting point.

Most Motorhome/Recreational Vehicle (RV) owners didn’t know the finer details of their engines. Typically they knew it was a “Detroit” and the number of cylinders. Info from bus/coach lines depended on the technical background of the person handling the sale.

Happily, a great deal of information about a Detroit motor can be deduced just from the engine number. An engine number that starts with or includes 6VF or 6VA is likely to be Series 92, and so on for the different series. On the Detroit engines the model number can be stamped immediately below the serial number. Sometimes the engine number recorded on the registration paperwork includes the complete or partial model number that could identify the engine type. For example, the last eight digits of 6VF08130480677840 gives the model number 8067-7840, which in Australia would be a 6V92TTA. (Because of different pollution standards many US sites will identify an 8067-7840 motor as a 6V92TA, except in California, where it would be a 6V92TTA).

The basic series naming convention is pretty logical: the initial digit is the number of cylinders, usually followed by a “V” for the cylinder configuration; the next two give the displacement in cubic-inches per cylinder (the 53, 71 and 92 series all follow this convention; later series , such as the 60 series, don’t). A“T” suffix indicates turbocharged; an“A” means aftercooled. Thus a “671” is a natually-aspirated 7 litre inline 6, while a “6V92TA” is a 9 litre turbocharged aftercooled V6. Some background on the Detroit diesels is available on Wikipedia (see Series 71, Series 92, and related pages). There’s a nice article here comparing the Detroits with similar-sized 4-stroke diesels for the moderately technically-inclined.

The tables below lists the SAE Rated Gross Power in kW and BHP (brake horsepower) for the various models, with links to the specification sheet for each. The rating is typically (but not always) at 2100 rpm. The same engine model can have different power ratings due to different injectors or other variations. There are some engines here that would never be fitted to a bus.

Series 53

Engine Model
numbers
Injectors Rated Gross Power
kW BHP
3-53 5033-7000 73
3-53T 5033-8300 98
4-53 5043-5101
5043-5201
5043-7000
S45
S45
N45
77
95
95
103
127
127
4-53 5043-7000 N50 101 136
4-53 5043-7101
5043-7201
S45 77
95
103
127
4-53T 5043-8301 N65 131 175
4-53T 5047-5340 5A60 127 170
6V53 5063-7000 N50 157 210
6V53T 5063-5300 5A55 174 233

Series 71

Engine Model
numbers
Injectors Rated Gross Power
kW BHP
3-71 1033-5000
1033-7000
81
81
4-71 1043-5000 N60 104 140
4-71 1043-5000 N65 113 152
4-71 +Torque Converter 1043-5001 N65 113 152
4-71 1043-7000 N60 104 140
4-71 1043-7000 N65 113 152
4-71T 1043-8300 N75 142 190
6-71 1063-5000 N65 170 228
6-71 1063-5000 N65 228
6-71 +Torque Converter 1063-5001 N65 170 228
6-71 1063-5100
1063-7000
N65 218
228
6-71 1063-7000 N65 170 228
6-71 1063-7100 N65 218
6-71T 1063-8300 N75 213 285
6-71T 1063-8340 7C75 205 275
6-71TT 1063-8740 7E75 172 230
6V71 7063-7000 N65 170 228
6V71 +Torque Converter 7063-7001 N65 170 228
6V71T 7063-7300 N75 195 262
8V71 7083-7000 N65 227 304
8V71 +Torque Converter 7083-7001 N65 227 304
8V71 7087-7040 7E65 227 304
8V71T 7083-7300 N75 261 350
8V71T 7087-7340
7087-7344
7087-7344
N75
N65
N70
350
308
335
8V71TA 7087-7640
7087-7640
7C75 269
276
360
370
8V71TT 7087-7340 N75 228 305
8V71TTA 7087-7940 7C75 228 305
12V71 +Torque Converter 7123-7001 340

Series 92

Engine Model
numbers
Injectors Rated Gross Power
kW BHP
6V92 8063-7000 80 201 270
6V92T 8063-7300 90 240 322
6V92TA 9290 250 335
6V92TTA 9290 201 270
8V92 8083-7000 9280 269 360
8V92T 8083-7300 9290 321 430
8V92TA 8087-7440 9A90 324 435
8V92TTA 8087-7840 9A90 272 365