Cummins ISB 6.7L Connecting Rod & Bearing Components Catalog

The connecting rod assembly in a Cummins ISB 6.7L engine is one of the most critical components in the rotating assembly, linking the piston to the crankshaft and converting linear motion into rotational power. A properly maintained and balanced connecting rod system ensures smooth operation, optimal fuel efficiency, and long service life for both marine and industrial applications.

At Diesel Pro Power, we supply premium-quality connecting rods, rod bearings, bushings, and cap bolts designed specifically for the ISB 6.7L and its related B Series family. Our inventory supports both fracture-split and non-fracture-split rod designs, as well as a full range of bearing sizes for standard and oversize applications.

Understanding the Cummins ISB 6.7L Connecting Rod Design

The Cummins ISB 6.7L utilizes two primary connecting rod designs depending on the year and configuration:

Non-Fracture-Split Connecting Rods

• Older design used in earlier ISB and B Series engines.

• Connecting rod caps are machined as a matched set, with smooth mating surfaces.

• Require precision alignment when replacing bearings or bolts.

• Commonly used in rebuilds where original rods are retained.

Fracture-Split Connecting Rods

• Modern design found in later ISB 6.7L engines.

• Rod caps are manufactured as a single piece and then “fracture-split” for a perfect interlocking fit.

• Offers improved strength and durability for high-performance or high-load environments.

• Cap and rod must remain paired—interchangeability is not possible.

Bearing Sets for Cummins ISB 6.7L

Rod bearings reduce friction between the connecting rod and crankshaft journal, ensuring smooth rotation and preventing metal-to-metal contact. We offer high-quality bearing sets for both rod styles:

Standard Size Rod Bearings

• Ideal for crankshafts within original factory specifications.

• Designed for proper oil clearance and lubrication.

• Available for both fracture-split and non-fracture rods.

Oversize Bearings (0.25 mm and 0.50 mm)

• Used when crankshaft journals have been machined undersize.

• Maintain correct oil clearance after crankshaft regrinding.

• Oversize thickness provides a precise fit for extended service life.

Cummins Connecting Rod Bushings

Rod bushings serve as the bearing surface for the piston pin (also known as a wrist pin), ensuring smooth pivoting motion during the piston’s travel.

• Manufactured to OEM specifications for the ISB 6.7L.

• Proper bushing installation prevents excessive piston pin wear and reduces the risk of engine knock.

• Recommended for replacement during any piston or rod service.

Connecting Rod Cap Bolts

Connecting rod bolts secure the rod cap to the connecting rod body and must maintain high clamping force under extreme combustion pressures.

Early-Style Bolts for Non-Fracture Rods

• Designed for reusable applications if they pass inspection.

• Should be replaced during major overhauls to ensure consistent torque and preload.

Bolts for Fracture-Split Rods

• Engineered for single-use in many applications.

• Precision fit to match the interlocking fracture-split surface.

• Replacement is highly recommended during any bearing service.

Applications for the Cummins ISB 6.7L Connecting Rod Components

The ISB 6.7L is widely used in marine propulsion, commercial vehicles, construction machinery, agricultural equipment, and stationary power units. Our connecting rod and bearing sets are suitable for:

• Cummins-powered fishing vessels and commercial marine applications.

• Heavy-duty generators and industrial pump systems.

• Agricultural tractors and harvesters with ISB 6.7L engines.

• Construction loaders, excavators, and cranes.

• Municipal service equipment such as snowplows and refuse trucks.

Maintenance & Replacement Recommendations

When to Replace Connecting Rod Bearings

• Low oil pressure or unusual engine knock under load.

• Metal shavings found in oil during maintenance.

• Scoring or pitting on the bearing surface.

• Routine overhaul intervals as recommended by Cummins.

When to Replace Connecting Rod Bushings

• Excessive piston pin clearance or visible scoring.

• Audible piston slap.

• During piston or rod replacement for preventative maintenance.

When to Replace Rod Cap Bolts

• Any sign of thread damage or stretching.

• As part of a complete rod rebuild.

• During any overhaul involving high-performance upgrades.

Installation Tips for Cummins ISB 6.7L Connecting Rod Components

• Cleanliness is critical—ensure all oil passages are free of debris before assembly.

• Always use a torque wrench and follow Cummins specifications for bolt torque and angle.

• Verify bearing clearance using plastigage or micrometer readings.

• Apply assembly lube to bearing surfaces before installation to prevent dry starts.

• Match rod caps to their original rods—especially critical for fracture-split designs.

Why Choose Diesel Pro Power for ISB 6.7L Connecting Rod Parts

• 40,000+ satisfied customers worldwide.

• OEM-spec components for guaranteed fit and performance.

• Stocked inventory for fast shipping.

• Bilingual customer support in English and Spanish.

• Trusted by marine operators, fleet mechanics, and industrial service centers.