Diesel C-12
Truck
Engine 380 hp
1450 lb-ft @ 1200 rpm Peak Torque
PERFORMANCE CURVES
1650
1450
1250
Torque
1050
lb-ft
850
650
450
400
Power
bhp 350
300
Shown with
Optional Equipment 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100
Engine Speed rpm
CATERPILLARâ ENGINE SPECIFICATIONS ENGINE RETARDATION
Performance – hp
Bore—in (mm) . . . . . . . . . . . . . . . . . . . . . . 5.1 (130) 500
Engine Brake
Stroke—in (mm). . . . . . . . . . . . . . . . . . . . . 5.9 (150) 400
Displacement—cu in (L). . . . . . . . . . . . . 732 (12.0) 300
Aspiration . . . . . . . . . . Turbocharged for ATAAC1 200
Rotation (from flywheel end) . . Counterclockwise 100
Cooling System 2 — gal (L) . . . . . . . . . . . . 2.7 (10.2) 1100 1300 1500 1700 1900 2100 2300
Lube Oil System (refill)— gal (L) . . . . . . . . 9.4 (36) Engine Speed rpm
Weight, Net Dry (approx)—lb (kg)
Data provided by Jacobs ® Vehicle Systems for Model 312A.
with standard equipment . . . . . . . . . 2070 (940)
PERFORMANCE DATA SIMULATED VEHICLE PERFORMANCE
Operating Range (rpm) . . . . . . . . . . . . . 1200-2100
MPG (TOA) Simulated Trip
Maximum Engine rpm . . . . . . . . . . . . . . . . . . . 2100 8.0
3.90:1
Advertised hp (kW) . . . . . . . . . . . . . . . . . . 380 (283)
Fuel Economy
Governed Speed — rpm . . . . . . . . . . . . . . . . . 2100 7.5 4.10:1
Max hp @ 1600 rpm (kW) . . . . . . . . . . . . 395 (295)
Peak Torque — lb-ft (N•m) . . . . . . . . . 1450 (1966) 7.0 3.90:1
Peak Torque — rpm . . . . . . . . . . . . . . . . . . . . . 1200
Torque rise (%) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 4.10:1
Altitude Capability — ft (m) . . . . . . . . 7500 (2288) 6.5
55 Cruise Speed mph 65
Simulated Transmission: Semi-Van 8.0' x 13.5'
Truck Spec 10 Speed (0.74 O.D.) Full Aero Package
C-12 380 hp Rear Axle Ratios: 275/80R 22.5 LP
4.10:1 — Performance GVW: 78 000 lbs
3.90:1 — Balanced
1
Air-to-Air AfterCooling
2
Engine only. Capacity will vary with radiator size and use of cab heater.
3
@ 65 mph “balanced”
C-12 DIESEL TRUCK ENGINE – 380 hp
STANDARD EQUIPMENT ELECTRONIC FEATURES
Crankcase breather
Electronic control module ■ Electronic self-diagnostics
Electronic data link, ATA/SAE ■ Electronically tabulated total fuel
Electronically controlled unit injector fuel system consumption, hours and miles
Fuel – spin-on filter, priming and transfer pumps ■ Electronically tabulated total idle time
Gear driven jacket water pump ■ Battery backup
Governor – full-range electronically controlled ■ Real time clock
Hydraulic steering pump drive, SAE A ■ Quick stop recorder
Lifting eyes
■ Fleet information software (FIS) capability
Lubricating – cooler, right hand filler, full flow
filter, gear-driven pump, front or rear sump pan ■ User-selectable, reprogrammable vehicle
operating parameters – vehicle mph speed
Turbocharger limiting, engine rpm speed limiting, cruise
control, intermediate gears and low gear
ACCESSORY EQUIPMENT limits, geardown protection, PTO vehicle mph
speed limit, PTO engine rpm speed limit,
Air compressor, gear driven, 13, 13.2, 16.5, or programmable idle rpm speed, idle shutdown
31 cfm timer, PTO ramp rate, top engine rpm limit,
Alternator, 12 Volt, 105 Ampere ambient temperature idle control
Dry charge coolant conditioner
Fan drive mounting bracket
Flywheel and SAE No. 1 housing
GEARING CONSIDERATIONS
Front engine supports
Jacobs engine brake Model 312A Caterpillar ® C-12 Air-to-Air Aftercooled (ATAAC)
Lubricating oil filter, bypass spin-on or Truck Engines offer a wide operating range and
centrifugal type high torque rise which promotes the use of
Rear power takeoff (1.31:1) transmissions with fewer gears. Even with this
SAE J1939 data link built-in feature, heavy/specialty haulers must
Starting, 12 Volt electric motor, ether starting aid remember their trucks should be geared to
achieve the appropriate compromise between
DIMENSIONS startability and desired road speed. Typical
49.75 in. loads of 80 000 Ib or less are less affected by
1263.7 mm 35.68 in. improper drive train specing than are heavy
50.6 in. 906.4 mm
1285.3 mm haulers. In general, either application shares one
similar recommendation – gear fast/run slow is
essential for good fuel consumption.
41.85 in.
1063 mm If any of the following conditions are present,
15.8 in. special attention should be given to proper
402.3 mm
transmission and axle specifications. A complete
Caterpillar Truck Engine Pro analysis is available
RATING DEFINITIONS AND CONDITIONS from your local Caterpillar or truck dealer.
1. Poor road surface
Performance is based on SAE J1349 standard
2. Adverse grades – 8% plus
conditions of 29.61 in. Hg (100 kPa) and 3. GVW in excess of 80 000 Ib
77° F (25° C).
For the best balance of performance and fuel
Fuel consumption is based on fuel oil having an economy on the C-12, spec axle ratios and tire
LHV of 18 390 Btu/lb (42 780 kJ/kg) and sizes to obtain:
weighing 7.001 lb/U.S. gal (839 g/L). 1475 rpm @ 60 mph
The curves shown are for a standard engine Subject to the following:
without fan, but equipped with air compressor Maximum recommended engine speed
and fuel, lubricating oil and jacket water pumps. at cruise – 1700 rpm
Additional ratings may be available for specific Minimum recommended engine speed
customer requirements. Consult your at 55 mph cruise speed – 1400 rpm
Caterpillar representative for details.
Materials and specifications are subject to change without notice. The International System of Units (SI) is used in this publication.
LEHT7899 Printed in U.S.A. © 1997 Caterpillar Inc.
Supersedes LEHT6109 All rights reserved.
