308C CR

Increased horsepower, better controllability, extended service intervals and a redesigned operator station increase your productivity and lower your operating costs.

Engine Model Mitsubishi 4M40E1
Net Power 54 hp
Gross Power 55 hp

Operating Weight 17730 lb
Operating Weight with Cab 17730 lb

Max digging depth - standard stick 13.45 ft
Max reach ground level - standard stick 20.67 ft
Center ground clearance 1.25 ft
Length to Center of Rollers 7.5 ft
Max cutting height - long stick 25.6 ft
Max cutting height - standard stick 24.2 ft
Max digging depth - long stick 15.4 ft
Max dump height - long stick 18.6 ft
Max dump height - standard stick 17.2 ft
Max reach ground level - long stick 22.2 ft
Max vertical dig depth - long stick 13.5 ft
Max vertical dig depth - standard stick 11.8 ft
Shipping Height 8.6 ft
Shipping Length 19.1 ft
Stick length - long stick 7.3 ft
Stick length - standard stick 5.5 ft
Swing radius - rear 4.2 ft
Track Gauge 6.1 ft
Transport Width 7.6 ft

Engine Dimensions
Bore 3.7 in
Stroke 4 in
Displacement 173 in3

Travel System
Travel Speed - High 3.3 mph

Hydraulic System
Operating Pressure - Equipment 3980 psi
Digging Forces - Stick (standard) 7850 lb
Digging Force - Stick (long) 6880 lb
Digging Force - Bucket 9820 lb
Digging force - bucket 9820 lb
Operating Pressure - Travel 4550 psi
Operating Pressure - Swing 3480 psi

Swing System
Machine Swing Speed 11.5 RPM

Service Refill Capacities
Cooling System 4 gal
Engine Oil 2.6 gal
Hydraulic Tank 14.5 gal
Fuel Tank 30.4 gal
Hydraulic System 24.3 gal

Compact Radius
Compact radius design delivers top performance in tight quarters.

Compact Radius

1) Front Swing From Center
  • 1665 mm (5 ft 6 in) stick - 1660 mm (5 ft 5 in)
  • 2210 mm (7 ft 3 in) stick - 2180 mm (7 ft 2 in) 2) Rear Swing From Center
  • 1290 mm (4 ft 3 in) 3) Overhang
  • 450 mm (18 in) shoes - 130 mm (5 in)
  • 600 mm (24 in) shoes - 55 mm (2 in) 4) Width
  • 2210 mm (7 ft 3 in) Stick - 3470 mm (11 ft 5 in)

Compact Radius Design
The 308C CR is a compact radius version of the 307C. It is designed to work in a 2850 mm (9 ft. 8 in.) wide area.

Shorter Tail Swing Radius
A shorter tail swing radius makes the 308C CR easier to operate against walls and in other tight areas, reducing the risk of damage to the rear of the machine during operation.

Flexibility in Tight Quarters
The shorter tail measurement allows the excavator to work productively in urban construction, on logging roads and other space-restricted sites.

The four-cylinder engine is built for power, reliability, economy and low emissions.


4M40-E1 Engine
The Mitsubishi 4M40-E1 engine was developed specifically for construction equipment. It features a long-stroke piston movement for high torque at medium to low speeds, excellent fuel efficiency and low sound levels and vibration.

Low Fuel Consumption
The engine offers low fuel consumption, improved thermal efficiency and reduced resistance between pistons and liners.

Cylinder Block and Head
The cylinder block is made of cast iron for improved wear resistance. The upper part is laser-hardened to reduce oil consumption, increase wear resistance and minimize piston ring scuffing. Aluminum alloy cylinder heads incorporate water directors to ensure efficient cooling.

Pistons and Rings
Heat-resistant aluminum cast alloy pistons feature clearance control struts. A short compression height results in high combustion efficiency and reduced weight. The piston ring set consists of three rings, treated for maximum wear resistance.

Crankshaft and Connecting Rod
The surface of the crankshaft journals and pins are induction-hardened to ensure high reliability. The forged connecting rods are made of a high-tensile strength steel alloy.

Cooling System
A large-diameter fan and full-length, water-cooled cylinders, combined with excellent thermal efficiency, help prevent overheating. The result is longer engine life and the ability to operate at high temperatures and under heavy loads. A mixed flow fan design provides high cooling efficiency. The core radiator is equipped with waved fins to prevent clogging.

Lubrication System
The system utilizes an external gear-type, high-efficiency oil pump. The large oil filter is composed of a main filter and a bypass filter, designed for high performance.

Starting System
The standard 308C CR has a 3.2 kW capacity starting motor, mounted at the right of the engine, and two Cat 100-AH capacity batteries. In this configuration, the machine can be started at -32ºC (-25ºF) with glow plugs.

Hydraulics deliver power and precise control to keep material moving at high volume.


Precise Control
Hydraulics deliver smooth changes in speed and outstanding overall control.

Pilot System
Increased pilot hydraulic pressure provides better control to the front linkage, swing and travel operations.

Component Layout
The 308C CR hydraulic system was designed to provide a high level of efficiency. With all major components located close together, shorter tubes and lines are needed, resulting in less friction loss in the lines and reduced pressure drops.

Hydraulic Cross-Sensing System
The system utilizes each of the main hydraulic pumps to 100 percent of engine power under all operating conditions, resulting in faster implement speeds and pivot turns.

Flow Control System
Pump flow decreases when controls are in neutral for reduced fuel consumption and sound levels.

Stick Regeneration Circuit
Saves energy while the stick is in use, providing shorter cycle times and lower operating costs.

Boom Drift Reducing Valve
This valve reduces the natural drift of the boom, so lifted material will remain suspended for long periods with virtually no drift.

Auxiliary Hydraulic Valve
The auxiliary hydraulic valve is standard on the 308C CR for use with optional hydraulic circuits.

Stackable Valves
One stackable valve can be used in combination with the main control valve, allowing additional tools to be added.

Auxiliary Hydraulic Arrangements
For maximum flexibility, three arrangements are available on the 308C CR: single function for a dedicated hammer, double function for a thumb or a combined function circuit.

Hydraulic Cylinder Snubbers
Snubbers are located at the rod-end of the boom cylinders and both ends of the stick cylinders to cushion shocks while reducing sound levels and extending cylinder life.

Front Linkage
Designed for maximum flexibility to keep productivity high on all jobs.

Front Linkage

Front Linkage Attachments
Allows the use of one boom, two sticks and four buckets. Using these combinations makes the excavator productive in a wide range of applications.

One-Piece Boom
The one-piece boom features a fabricated box-section design. Robotic welding and high-tensile strength steel on upper, lower and side plates provide high durability and consistency.

Two stick attachments are available: a long stick to maximize reach or a medium stick for the most versatile front linkage. Both sticks use a box-section design made of high tensile-strength steel and a buffer plate.

Linkage Bearings
A self-lubricated, sintered bearing greatly extends the greasing interval on front linkage pins by reducing pin friction. Greasing intervals on the bucket swing pin connection are also extended using a mesh bearing design.

High-tensile-strength steel is used in high-stress areas for excellent wear and shock resistance. The side plates are tapered to prevent contact of the bucket sidewalls during trenching operations. All four bucket sizes have a general-purpose design and share a common side profile.

Bucket-Flop Adjustment Mechanism
Allows the operator or service person to reduce the side play at the bucket to stick-nose connection. This attachment is only available when Cat buckets are ordered.

Undercarriage and Blade
Durable undercarriage absorbs stresses and provides excellent stability.

Undercarriage and Blade

Undercarriage Design
The 308C CR uses a standard undercarriage with the same basic design as the 307C, ensuring high reliability.

Grease-Lubricated Track
Grease-lubricated seals protect the track link and provide longer wear life by helping to keep dirt and debris from entering the pin and bushing joint.

Roller Lubrication
All rollers, sprockets and idler joints are closed with floating seals. Lubricating oil from the seals prevents water and dirt from entering. The seals also make lubrication maintenance-free.

Carbody and Track Roller Frame
X-shaped, box-section carbody provides high rigidity and excellent resistance to torsional bending. The track frame is made from a press-formed pentagonal section for maximum strength and long service life. The carbody and track roller frames use robotic welding to ensure continuous, high-quality welds. Long welds contribute to smoother transition of loads and increased durability.

Travel Motors
Automatic speed selection enables the machine to automatically shift up and down from high and low speeds in a smooth, controlled manner. An "anti-hunt" feature eliminates the hunting often associated with auto shifting when operating near the shift point.

Travel Brake Valves
An improved counterbalance valve eliminates sudden starts and stops during travel. A cross-over relief valve helps reduce shocks during acceleration and deceleration and decreases wear on the travel motors.

Idler Guard
An idler guard is integral to the track roller frame. This standard guard helps maintain track alignment while traveling or working on slopes.

Triple Grouser Shoes with Rubber Pads
The 308C CR standard shoe has four extra holes for installation of steel-backed rubber street pads. Optional rubber pads are attached to the track shoes, eliminating potential damage to paved road surfaces. (Pads are installed by your local Caterpillar dealer or can be purchased through the dealer for later installation.)

Segment-type Rubber Track
Optional segment-type rubber track prevents damage to concrete and other road surfaces, especially in urban areas.

Two blade widths are available as attachments. The bolt-on cutting edge consists of three pieces, which can be reused by turning them upside down. Replaceable bolt-on edges protect the blade from damage and wear. Mesh bearings in the pin joints of the blade cylinder extend the greasing interval.

Operator Station
Designed for simple, easy operation, the 308C CR allows the operator to focus on production.

Operator Station

Cab Design
An enlarged cab with curved styling gives the operator a comfortable, spacious working environment and improved visibility.

The low-back seat slides forward and backward independent of the consoles, so it can be adjusted to the operator's comfort level.

Sliding Door
The cab door slides alongside the cab and takes less space to open and close than a hinged door. This unique design allows the operator to easily get in and out of the cab when working against walls on job sites, even when attachments are added.

Redesigned consoles feature a simple, functional design. Both consoles have attached adjustable armrests and slide forward and backward.

The conveniently located compact monitor displays instrument panel gauges and indicators in an easy-to-read and understand format.

Cab Mounts
The cab shell is attached to the frame with viscous rubber cab mounts, which dampen vibrations and sound levels while enhancing operator comfort.

Travel Control Levers
The two travel control levers have a reverse-L shape, making them easier to operate. Lever stroke and force have been adjusted to improve fine control and to prevent jolting during machine impact.

Hydraulic Activation Control Lever
For added safety, this lever must be in the locked position before the operator can leave the cab. This feature prevents the machine from operating without the operator in the cab.

Climate Control
Fully automatic climate control adjusts temperature and flow.

Window glass is attached directly to the window frame with adhesive to improve visibility. An enlarged skylight with sunshade improves overhead visibility.

The front windshield can be opened and closed using a one-touch action release system and autolock system.

Pillar-mounted wipers increase the operator's viewing area.

Standard Cab Equipment
To enhance operator comfort, the cab includes a radio, beverage holder, ashtray, coat hook and storage compartment.

Control Pattern Changer
A control pattern changer is available as an attachment. It allows the operator to select from ISO and BHL patterns with a single movement. When the 308C CR is shipped from the factory, the control pattern is set to the ISO pattern.

Simplified service and maintenance save you time and money.


Extended Service Intervals
Extended service and maintenance intervals reduce service time and machine availability. Use of oil-free bearing extends front linkage greasing interval to 1,000 hours, except in bucket area.

Ground-Level Maintenance
For operator convenience, most daily maintenance areas can be easily reached from ground level.

Fan Guard
Engine radiator fan is completely enclosed by fine wire mesh, reducing the risk of injury.

DT Electrical Connectors
Connectors are water- and vibration-resistant, improving electrical system reliability.

Radiator and Pump Compartment
Opening the engine hood allows easy access to the engine radiator and the oil cooler. A reserve tank and drain cock are attached to the radiator to simplify maintenance.

Air Filter
Cat radial seal provides superior cleaning efficiency.

Engine Inspection
The engine can be accessed from the upper structure or from under the machine. The engine hood incorporates a gas cylinder-assist mechanism, making the hood easy to open. A steel wall separates the engine and pump compartments, preventing hydraulic oil from spraying on the engine in the event of a hydraulic line failure.

Engine Maintenance
To make daily servicing easier, the oil level gauge, oil filter, fuel filter and priming pump are grouped on the left side of the engine.

Fuel Tank
A drain cock is installed at the bottom of the tank, making it easier to remove water and sediment during maintenance.

Fuel-Water Separator
The water separator has a primary fuel filter element and is located in the radiator compartment for easy access from the ground.

Storage Box
The storage box is located at the right front of the upper structure and can be locked. Tools and other repair equipment can be stored in this space.

Complete Customer Support
Cat dealer services help you operate longer with lower costs.

Complete Customer Support

Make detailed comparisons of the machines you are considering before you buy. What are the job requirements, machine attachments and operating hours? What production is needed? What is the true cost of lost production? Your Cat dealer can give precise answers to these questions.

Look past the initial price; look at the value the 308C CR offers. Consider the resale value and compare productivity and day-to-day operating costs. Consult your local Cat dealer for financing options.

For the best operating techniques to increase productivity and your profit, turn to your Cat dealer for the latest training literature and trained staff.

Repair option programs guarantee the cost of repairs up front. Diagnostic programs such as Scheduled Oil Sampling and Technical Analysis help you avoid unscheduled repairs.

Repair, rebuild or replace? Your Cat dealer can help you evaluate the cost involved so you can make the right choice.

Product Support
You will find nearly all parts at our dealer parts counter. Cat dealers utilize a worldwide computer network to find in-stock parts to minimize machine downtime. You can save money with Cat remanufactured components.

Your local Cat dealer is there to support and protect you. Extended warranty options are also available.

Standard Equipment

Alternator, 35 amp
Automatic swing parking brake
Auxiliary hydraulic valve
Batteries, heavy-duty
  • Air conditioner with defroster
  • AM/FM radio
  • Ash tray
  • Beverage holder
  • Coat hook
  • Floor mat
  • Horn
  • Instrument panel and gauges
  • Joysticks, pilot-operated
  • KAB T1P seat with adjustable armrest, without head rest
  • Lighting, interior
  • Literature compartment
  • Neutral lever (lockout) for all controls
  • Openable front windshield
  • Openable skylight
  • Pillar mounted windshield wiper and washer
  • Rear window emergency exit
  • Seat belt
  • Travel control pedals with hand levers
  • Utility space for magazines
Door and caps lock with one-key security system
Mirrors (cab rear and left)
  • MMC 4M40-E1 Diesel engine
  • 24-volt electric starting
  • One touch low idle
  • Cooling system
  • Water separator
  • Two speed auto-shift travel
  • Straight line travel
  • Muffler
Reverse swing damping valve
  • Hydraulic track adjusters
  • Track-type undercarriage with grease lubricated seals
  • Idler end track guiding guards
  • 450 mm (18") triple grouser shoes with additional holes for mounting rubber street pads
Working light, chassis mounted

Optional Equipment

Auxiliary hydraulic lines for sticks and boom
Blade, 2320 mm (7'7"), for use with 450 mm (18") steel or segment rubber track
Blade, 2470 mm (8'1"), for use with 600 mm (24") track
Bucket linkage
Cab mounted working lights
Coolant, extended life -50° C (-58° F)
Front windshield guard
Hand control pattern changer
Hydraulic arrangements, auxiliary:
  • single-function capability
  • double-function capability
  • combined single and double function capability
Power supply 12V-5A (cigar lighter type)
Right-side boom lights
Stick and boom combinations:
  • 3.7 m (12'2") boom with left side light
  • 2.21 m (7'3") stick
  • 1.67 m (5'6") stick
  • 600 mm (24") triple grouser
  • 450 mm (18") segment rubber track
Travel alarm (mandatory in certain countries)
Vandalism guard



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