New 3909888 Fan Blade Hub FAN SUPPORT for Cummins 4B 4BT 6BT Fan Hub 4932912

Fan Blade Hub for Cummins

This fan blade hub (fan support) with OEM cross-reference numbers 3909888 and 4932912 mounts the cooling fan on Cummins 4B, 4BT, and 6BT engines to maintain proper airflow through the radiator.

Overview

This fan blade hub assembly replaces OEM parts 3909888 and 4932912 and is designed for Cummins 4B, 4BT, and 6BT diesel engines. It supports the engine cooling fan securely while allowing smooth rotation to draw air across the radiator. The hub is built to withstand high rotational speeds and thermal cycling common in heavy-duty applications.

Built For Performance

• Machined from cast iron for strength and vibration damping
• Precision bearings reduce friction and extend service life
• Integrated pilot alignment ensures concentric fan mounting
• Pre-drilled bolt pattern matches OEM fan blade configurations
• Heat-treated flange resists warping from engine heat

Fits These Machines

• for Cummins 4B
• for Cummins 4BT
• for Cummins 6BT
• for engines using fan hub part 4932912

On-The-Job Use

• Replacing worn or broken fan supports in industrial generators
• Restoring cooling system integrity in agricultural tractors and combines
• Rebuilding fan drive assemblies on construction equipment like excavators

Specs At A Glance

Good To Know

Q: Is this fan hub compatible with aftermarket fan blades? A: Yes, the hub accepts standard 4-bolt pattern fan blades commonly used on Cummins engines, but verify blade bolt spacing before installation.

Q: How do I know if the fan hub needs replacement? A: Signs include wobbling fan blades, unusual noise from the front of the engine, or visible wear on the bearing seal.

Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.