Cummins 6BT Connecting Rods & Related Components

The connecting rod is a critical component in your Cummins 6BT engine, acting as the mechanical link between the piston and the crankshaft. It must withstand extreme forces during each combustion cycle while maintaining precise alignment for efficient engine operation. At Diesel Pro Power, we supply premium-quality connecting rods and all related components—including bearings, bushings, and cap bolts—for both fracture-split and non-fractured rod designs used in the Cummins B Series family. With over 40,000 satisfied customers worldwide, we ensure every part meets OEM specifications for performance, durability, and reliability.

Understanding the Connecting Rod in the Cummins 6BT

The Cummins 6BT connecting rod has two main functions:

1. Transmit Power – It converts the linear motion of the piston into rotational motion for the crankshaft.

2. Maintain Stability – It keeps the piston aligned within the cylinder while withstanding extreme combustion pressures.

There are two main designs found in the 6BT platform:

• Non-Fractured (Conventional) Connecting Rods – These use a machined cap and body, held together with cap bolts. They require precision machining and matching during assembly.

• Fracture-Split Connecting Rods – Manufactured with a controlled break along the cap joint, creating an interlocking surface that improves strength and alignment.

Diesel Pro Power supplies both versions, ensuring compatibility with the exact build of your Cummins 6BT.

Connecting Rod Options for Cummins 6BT

Standard Non-Fractured Connecting Rods

Designed for earlier versions of the Cummins B Series, these rods feature a machined mating surface between the rod body and cap. They are ideal for rebuilds on legacy engines where precision machining and traditional assembly methods are preferred.

Fracture-Split Connecting Rods

These modern rods are manufactured to break along a controlled line during production, creating a perfectly matched cap and rod body. This process enhances strength, alignment, and longevity—especially in high-compression or heavy-duty marine and industrial applications.

Bearing Sets for Cummins 6BT Connecting Rods

A connecting rod rebuild is never complete without new bearings. These bearings allow smooth pivoting of the rod on the crankshaft while preventing metal-to-metal contact. We carry bearings for both non-fractured and fracture-split rods, available in standard and oversize dimensions for precision fitment.

Bearing Sizes Available

• Standard Size Bearings – For crankshafts in original, unworn condition.

• 0.25 mm Oversize Bearings – For crankshafts that have been reground to the first undersize specification.

• 0.50 mm Oversize Bearings – For crankshafts machined to the second undersize specification.

Each set includes both the upper and lower shells to service one connecting rod.

Cummins 6BT Connecting Rod Bushings

Located at the small end of the connecting rod, the bushing supports the piston pin and ensures smooth movement during each stroke. Over time, bushings can wear, causing piston pin noise, poor lubrication, or misalignment. Diesel Pro Power offers premium bushings for all Cummins B Series variants, including 4B, 4BT, 6B, 6BT, ISB, and QSB models.

Connecting Rod Cap Bolts for Cummins 6BT

Cap bolts are responsible for holding the rod cap securely in place under extreme combustion pressure. Using the correct bolt type for your rod design is essential:

• Early-Style Bolts – For non-fractured connecting rods, used in earlier Cummins B Series engines.

• Fracture-Split Bolts – Specifically designed for fracture-split rods, with precise tensile properties for long-term reliability.

Replacing these bolts during a rebuild is strongly recommended, as reusing worn bolts can compromise engine performance and safety.

Choosing the Correct Parts for Your Cummins 6BT

When rebuilding or replacing connecting rod components, it’s important to match parts to your engine’s exact specifications. Here are a few tips:

1. Identify Your Rod Type – Determine if your engine uses non-fractured or fracture-split connecting rods.

2. Measure Bearing Size – Use a micrometer to measure your crankshaft journals and select standard or oversize bearings accordingly.

3. Replace Bushings and Bolts Together – This ensures all load-bearing and fastening components are fresh and ready for service.

4. Follow Torque Specifications – Always use Cummins-recommended torque values when installing cap bolts.

Applications of the Cummins 6BT Connecting Rod

The Cummins 6BT is widely used in both marine and industrial applications, including:

• Commercial fishing vessels

• Tugboats and ferries

• Agricultural and irrigation pumps

• Heavy-duty industrial generators

• Construction equipment

In all these environments, connecting rod reliability is crucial. High-load cycles, long operating hours, and varying engine speeds mean your rod assembly must be in top condition.

Diesel Pro Power Advantage

When you order Cummins 6BT connecting rod parts from Diesel Pro Power, you get:

• Worldwide Shipping – Fast delivery to over 180 countries.

• OEM Quality – Parts that meet or exceed factory specifications.

• Expert Support – Guidance from our team of diesel engine specialists.

• Proven Track Record – Trusted by over 40,000 customers for marine and industrial diesel parts.