MaxxForce®

MaxxForce® 9: Overview

The MaxxForce® 9 is built on the same proven I-6 platform as Navistar’s legendary and industry-leading DT engine. This I-6 design grew from a big idea: bring to the mid-range diesel market traditional big bore features like wet-sleeve design and in-chassis rebuild capability.  This model, which brings increased 9.3-liter displacement by longer stroke, meets the requirements of more demanding applications.

The MaxxForce 9 adds to the reliable and durable platform premium features like dual sequential turbo technologies, single-piece gallery-cooled steel pistons, and crankcase adder reinforcement.

MaxxForce® 9: Reliability & Durability

Reliability

A rock-solid, time-tested platform ensures legendary reliability. For the new generation, Navistar engineers carried forward the proven technologies and components like:

• Premium plateau-honed cylinder design
• Reinforced bearing-cap ladder
• Durable roller cam followers

For changes outside the base engine design, the intention was to further improve reliability. Foremost among these changes are dual sequential free-wheel turbochargers and a premium wiring harness, which utilizes a single foam-molded design that locks down wiring and secures connections.

Durability and Resale Value

These engines feature the same precision-machined wet-sleeved design that provides heavy-duty engine durability. Six bolts per cylinder provide headgasket integrity unmatched by competitive four-bolt designs. Premium valvetrain components and low-friction design further increase engine life. Adding to the appeal of this engine is its ability to be completely re-built in-frame. As a result, the engine can be returned to original factory specifications for a lot less than the cost of remanufacturing, which gives them a strong value advantage at re-sale. Over the past 10 years, the average residual value of MaxxForce-powered International medium-duty trucks has outpaced the competition by 12–19 percent.

Premium Valvetrain

Roller-cam followers provide increased durability, longer valve and camshaft life, and slow valve lash growth compared with competitive flat tappets. Replaceable valve seats and guides allow for easy cylinder head rebuild. Four valves per cylinder provide better breathing, performance and lower emissions.

Advanced High-Pressure Fuel System

The electro-hydraulic high-pressure fuel system features new high-efficiency injector nozzles and advanced electronic control strategies for fuel economy gains.

Improved Air-Management System

A new regulated two-stage turbocharger and upgraded cooling system provide outstanding boost and response for every application.

• Single-piece gallery-cooled steel pistons bring longer life, and reduced blow-by and oil consumption.
• Significantly larger main bearings than most competitors result in heavy-duty durability.
• Foam-molded wiring harness secures wiring and connections for increased reliability and durability.
• Two-Stage turbocharger for increased durability for higher horsepower applications.
• The crankcase features six head bolts per cylinder, which provides even clamping for headgasket life that competitive four-bolt designs can’t match.
• Crankcase ladder reinforcement provides added strength and rigidity, maintaining perfect alignment of crankshaft under heavy loads, all while reducing engine noise.
• Precision-machined wet sleeves result in even cylinder cooling and unmatched structural integrity.

MaxxForce® 9: Wide Vocational Capability

The MaxxForce 9 and 10 are purpose-built to the needs of International customers.  They are compatible with a full range of automatic and manual driveline options and thousands of potential build configurations to serve the broadest range of on- and off-highway applications. Six different model ratings offer 300-350 hp and 860-1150 lb.-ft. of torque. Shift energy management technology allows for higher peak torque when used with select transmissions.

MaxxForce® 9: Engine Specs and Ratings

• Engine Type: Diesel, 4-Cycle
• Configuration: Inline 6-Cylinder
• Displacement: 9.3 L (570 cu. in.)
• Bore & Stroke: 4.59 in. & 5.75 in. (11.7 cm & 14.6 cm)
• Compression Ratio: 17.2:1
• Aspiration: Two-Stage Turbochargers, Intercooler & Aftercooler
• Combustion System: Direct Injection
• Engine Lubrication: 30 Quarts (28 L)
• Total Engine Weight (Dry): 1,425 lbs. (646 kg)
• Dimensions: L 45 in. x W 42 in. x H 47 in. (L 114 cm x W 107 cm x H 119 cm)
• Valves: 4 Valves per Cylinder

MaxxForce® 9: Serviceability

MaxxForce I-6 engines now feature a host of design improvements that further boost serviceability. These include two turbochargers, single-unit EGR valve, mixer, grid heater and throttle housing, single unique key diagnostic connection and improved accessibility locations of key systems and components.

• Single-box 32-bit ECM has fewer connection points for added reliability and easier serviceability.
• Maintenance-free closed crankcase ventilation system features a centrifugal oil mist separator, which means there are no filters to change.

Preventive Maintenance Intervals

• Change Engine Oil, Replace Oil Filter: Up to 15,000 miles (24,140 km) / 6 months / 550 hours / 2,100 gallons (7,949 L)
• Replace Fuel Filter: 30,000 miles (48,280 km) / 12 months / 1,100 hours / 4,200 U.S. gallons fuel
• Replace Coolant*: 300,000 miles (482,803 km) / 5 years / 12,000 hours

*Add Extended Life Coolant (ECL) Extender @ 150,000 miles (241,400 km) / 30 months / 6 ,000 hours