Request Info

Contact Us For Price


Maximum Rating425 BHP (317 bkW)
EmissionsNSPS Site Compliant Capable or Non-regulated
Displacement1099 in³ (18 l)
Minimum Rating425 BHP (317 bkW)
Tough and durable, built on the industry-standard G3400 platform bring maximum uptime and low operating cost to your operation. G3408C engines meet the most demanding continuous duty gas compression applications with virtually no unscheduled downtime.Ideal applications for G3408C engines include gas lift, gas gathering, and wellhead gas compression. Cat G3408C gas engine. Ratings: 317 bkW (425 bhp) @ 1800 rpm are NSPS site compliant capable with customer-provided aftertreatment or available for non-regulated areas.


Maximum Rating425 BHP (317 bkW)
EmissionsNSPS Site Compliant Capable or Non-regulated
Displacement1099 in³ (18 l)
Minimum Rating425 BHP (317 bkW)
Compression Ratio8.5:1
Rotation from Flywheel EndCounterclockwise
Flywheel and Flywheel HousingSAE No. 0
Flywheel Teeth136
Weight - Dry4950 lb (2245 kg)
Cooling System14.5 gal (US) (54.9 l)
Lube Oil System - Refill39 gal (US) (147.63 l)
Oil Change Interval750 hours
Ignition, ProtectionCat EIS
Stroke6 in (152 mm)
Bore5.4 in (137 mm)

Benefits and Features

• Improved reliability and durability • Ability to burn a wide spectrum of gaseous fuels • Robust diesel strength design prolongs life and lowers owning and operating costs• Broad operating speed range

Meets U.S. EPA Spark Ignited Stationary NSPS Emissions for 2007/08

Lean-burn engines operate with large amounts of excess air. The excess air absorbs heat during combustion reducing the combustion temperature and pressure, greatly reducing levels of NOx. Leanburn design also provides longer component life and excellent fuel consumption.

Detonation sensitive timing protects the engine against detonation damage. Higher voltage and longer spark duration mean easier starts, fewer misfires, and smoother operation. Diagnostic codes help pinpoint cylinder and component of interest. Spark plug maintenance codes identify spark plug condition

• Deep sump oil pan has a larger capacity for normal 750-hour oil change intervals• Side covers on block allow for inspection of internal components

Large variety of factory-installed engine attachments reduces packaging time

Every engine is full-load tested to ensure proper engine performance.

GERP is a web-based program designed to provide site performance capabilities for Cat natural gas engines for the gas compression industry. GERP provides engine data for your site's altitude, ambient temperature, fuel, engine coolant heat rejection, performance data, installation drawings, spec sheets, and pump curves.

More than 2,200 dealer outletsCaterpillar factory-trained dealer technicians service every aspect of your petroleum engineCat parts and labor warrantyPreventive maintenance agreements available for repair-before-failure optionsS•O•SSM program matches your oil and coolant samples against Caterpillar set standards to determine:- Internal engine component condition- Presence of unwanted fluids- Presence of combustion by-products- Site-specific oil change interval

Over 60 years of natural gas engine productionOwnership of these manufacturing processes enables Caterpillar to produce high quality, dependable products.- Cast engine blocks, heads, cylinder liners, and flywheel housings- Machine critical components- Assemble complete engine

For all your petroleum power requirements, visit

Standard Equipment

  • Air cleaner — single element with service indicator
  • Electronic governor
  • Air/fuel ratio control
  • Thermostats and housing
  • Jacket water pump
  • Aftercooler water pump
  • Aftercooler core
  • Watercooled exhaust manifolds
  • Dry exhaust elbow
  • SAE No. 0 flywheel
  • SAE No. 0 flywheel housing
  • SAE standard rotation
  • Gas pressure regulator (1.5 to 5 psi gas supply required)
  • Natural gas carburetor
  • Cat Electronic Ignition System (EIS) with detonation sensitive timing
  • Service meter
  • Crankcase breather — top mounted
  • Oil cooler
  • Oil filter — RH
  • Oil pan — deep sump
  • Oil filler — RH in valve cover and RH dipstick
  • Engine supports
  • Detonation sensitive timing control
  • Shutoff
  • Paint — Cat yellow
  • Crankshaft vibration damper and pulleys
  • Lifting eyes
  • Cylinder block inspection covers

Optional Equipment

  • Air cleaner — two-stage
  • Air inlet adapter
  • Precleaner
  • Air cleaner rain cap
  • Battery chargers
  • Charging alternators
  • Ammeter gauge
  • Ammeter gauge and wiring
  • Control mounting
  • Radiators
  • Blower fan and fan drives for customer suppliedradiators
  • Expansion tank
  • Heat exchangers
  • Flexible fittings
  • Elbows
  • Flanges
  • Rain caps
  • Mufflers
  • Exhaust manifold — instrument holes at each port
  • Dual gas regulator
  • Carburetor kits
  • Fuel filter
  • CSA ignition
  • Ignition ground wiring harness
  • Power supply
  • Alarm module
  • Gauges and instrument panels
  • Vibration isolators
  • Auxiliary drive pulleys
  • Enclosed clutch and clutch support
  • Front stub shaft
  • Flywheel stub shaft
  • Pulley removal
  • Gas valves
  • Status control box interconnect wiring harness
  • Air starting motor
  • Air pressure regulator
  • Air silencer
  • Electric start control
  • Electric starting motors — single 24V
  • Starting aids
  • Battery sets — (24V dry), cables, and rack
  • Special paint