MaxxForce® 11 - Big Bore: Overview
To succeed in a competitive business, you need an engine and an organization behind it that are always performing and working for you. Navistar’s MaxxForce® Big Bore engines have revolutionized how the world looks at Class 8 commercial diesels.
Designed specifically for International® brand heavy vehicles, with a combination of technologically advanced materials and components, these engines deliver outstanding fuel economy, excellent power characteristics, an exceptionally smooth and quiet ride, and high strength without added weight. And they’re backed by the largest dealer and service network in North America.
Those advantages ensure your business will be “Always Performing.”
You need Flash 9 or above to view this content.

MaxxForce® 11 - Big Bore: The Four Pillars
Outstanding Fuel Economy
Technologies responsible:
- High-pressure common-rail fuel system
- Dual sequential Turbochargers
- Innovative heat-management system
- Low-friction design
Key advantages:
- Low cost of ownership
- Enhanced performance
Excellent Power Characteristics
Technologies responsible:
- High-pressure common-rail fuel system
- Dual sequential Turbochargers
Key advantages:
- Peak torque at 1,000 rpm
- Better reponse for earlier up-shifts
- Better lugging for fewer downshifts
Low Noise, Vibration And Harshness
Technologies responsible:
- High-pressure common-rail fuel system
- Integral ribs in the cylinder block
- Isolated oil pan
Key advantages:
- Exceptional driver comfort and reduced fatigue
- NVH that approaches the levels of a gasoline engine
High Strength Without Added Weight
Technology responsible:
- Compacted-graphite iron cylinder block
Key advantage:
- Extremely strong block foundation for long service life without excess weight
Service
- Uptime though dealer support network of 587 dealers across the United States, Canada and Mexico
MaxxForce® 11 - Big Bore: HPCR
A major key to MaxxForce Big Bore performance is its advanced fuel system, which features injection pressures of 2,200 bar (approximately 32,000 psi), for precise fuel dosing, injection timing and optimal combustion. The results: better fuel efficiency, quieter operation and in-cylinder reduction of emissions.
Goes The Extra Mile. Per Gallon.
MaxxForce Big Bore engines combine the most advanced engine technologies to deliver more torque and responsiveness at low rpm for outstanding fuel efficiency. A high-pressure common-rail fuel system, dual staged turbos, innovative heat-management system and low-friction design convert the highest percentage of your fuel into power you can use. And that adds up to low cost of ownership.
MaxxForce® 11 - Big Bore: Twin-Series Turbochargers
Dual Turbos and Advanced Air-Management
MaxxForce Big Bore engines use dual staged turbochargers to deliver powerful performance from stop light to mountaintop. The smaller, primary turbo responds quickly for immediate take-off at low engine speeds, and the larger, secondary turbo provides peak power at higher speeds and on steep grades. Peak torque is achieved at 1,000 rpm and holds steady to 1,200 rpm, a much lower engine speed than other big bore engines. This reduces gear-shifting needs uphill and allows for shifting at lower speeds when accelerating.
Big Power From Stop Sign to Ridgeline
One look at the MaxxForce Big Bore power curves tells the story. Dual staged turbos and a high-pressure injection system help deliver peak torque at 1,000 rpm versus typical 1,200 rpm for competitors. All the power you need, whenever and wherever you need it.
MaxxForce® 11 - Big Bore: CGI and Low Friction Design
Compacted-Graphite Iron Block
How can MaxxForce deliver outstanding fuel efficiency, emissions control without SCR, quiet operation and maximum durability? A key component is the Class 8 industry’s only CG Iron block. This incredibly strong platform handles the loads that deliver the best fuel combustion and damps vibration and noise. It carries the load without weighing you down.
Strong as a Rock. Light as a Feather.
Because CG Iron is so incredibly strong, castings don’t have to be as thick and heavy in order to achieve the desired durability required for heavy-duty diesel. This results in up to 500 pounds of weight savings over traditional big bore engines cast from gray iron — which can translate to greater payload and bigger payback.
Maximum Reliability and Durability
MaxxForce Big Bore engines are built on a block of compacted graphite iron, a material far stronger than conventional grey iron. CG Iron provides superior strength, less fatigue and years and years of reliable service.
Quietly Goes About Your Business
The advanced, ribbed CG Iron block and high-pressure multi-shot injection system combine to produce 30% lower noise inside the cab and much lower vibration for increased driver comfort. It’s also startlingly quiet outside, at idle and in action. The smooth, quiet ride of the MaxxForce Big Bore will take you by surprise. See and hear the difference at www.MaxxForceBigBore.com.
MaxxForce® 11 - Big Bore: Engine Specs and Ratings
- Engine Type: Diesel, 4-cycle
- Configuration: Inline 6-cylinder
- Displacement: 10.5 L (641 cu. in.)
- Bore and Stroke: 4.72 in. & 6.10 in. (12 cm & 15.5 cm)
- Compression Ratio: 16.5:1
- Aspiration: Dual Staged Turbochargers, Intercooler & Aftercooler
- Combustion System: Direct Injection
- Lubricating System Capacity: 42 quarts (40 L)
- Total Engine Weight (dry): 2,400 lbs. (1,089 kg)
- Dimensions: L 59 in. x W 37 in. x H 49in. (L 150 cm x W 94 cm x H 125 cm)
- Valves: 4 Valves Per Cylinder, Overhead Cam Actuated
MaxxForce® 11 - Big Bore: Serviceability
Ease of service also sets these new model MaxxForce Big Bore engines apart, because uptime for you is top of mind for us. All key systems and components are easily accessed, from valve cover to oil filter to fuel filter. A single ECM and fewer electrical connections throughout mean less diagnostic and maintenance time.
Preventative Maintenance Intervals
- Change Engine Oil, Replace Oil Filter: 25,000 miles / 12 months / 1,100 hours / 4,200 gallons
- Replace Fuel Filter: 25,000 miles / 12 months / 1,100 hours / 4,200 gallons
- Replace Coolant*: 600,000 miles / 6 years / 12,000 hours
*Add Extended Life Coolant (ELC) Extender @ 300,000 miles / 3 years / 6,000 hours
MaxxForce® 11 - Big Bore: Wide Vocational Capability
Versatility, With Available Options:
- Optional engine compression retarder brake
- Programmable electronic parameters for increased fuel economy
- Optional integral rear PTO for mixer applications
- Optional front-end PTO for plow and other applications