4N4385 Pinion Rotor for Caterpillar

The 4N4385 is a pinion rotor for air starter motor applications on Caterpillar equipment. It is used with Caterpillar engines, generator sets, generators, and industrial engines, including the 3304, 3306, 3304B, 3306B, SR4, and G3304 models.

This is a new aftermarket spare part manufactured by CTP (Costex Tractor Parts).

The part designation is Pinion Rotor, and the identifying part number is 4N4385. The component belongs to the air starter motor category and is listed for use in equipment and power-generation applications manufactured by Caterpillar.

Fitment

• Caterpillar 3304 engine
• Caterpillar 3306 engine
• Caterpillar 3304B engine
• Caterpillar 3306B engine
• Caterpillar SR4 equipment
• Caterpillar G3304 engine

The available application data identifies the 4N4385 pinion rotor for the following Caterpillar equipment groups:

• Caterpillar engine-machine applications
• Caterpillar engine-generator set applications
• Caterpillar generator applications
• Caterpillar industrial engine applications

The listed model information covers the Caterpillar 3304, 3306, 3304B, 3306B, SR4, and G3304 series. The part is described for air starter motor assemblies used with these equipment and engine applications.

Specifications