PAI Industries, Inc. REAR CRANKSHAFT SEAL Part No: 336012

$26.43

The PAI 336012 Rear Crankshaft Seal is designed for heavy-duty Caterpillar engines (3406, 3406E, 3408, C15, C16, C18 series) and replaces OEM references such as 142-5868, 2W-1734 and 4P-2734. Built to meet rigorous performance standards, it provides reliable sealing at the rear crankshaft under high heat and pressure. Available from Wofford Truck Parts, this seal is ideal for rebuilds or maintenance to prevent oil leaks and maintain engine integrity.

Specifications

The PAI 336012 Rear Crankshaft Seal (offered by Wofford Truck Parts) is a premium aftermarket replacement for the rear main seal position on a wide range of heavy-duty Caterpillar engine families. According to the product specification, it has dimensions: free ID 6.06″ (≈153.92 mm) × OD 7.34″ (≈186.43 mm) × thickness 0.75″ (≈19.05 mm).

It is designed for engine families including the CAT 3400 / 3406 / 3406E / 3408 series, and the C15 / C16 / C18 series engines. The seal replaces OEM CAT part numbers such as 142-5868, 2W-1734, 4P-2734, 130-8107, thereby providing a direct fit for engine rebuilds or maintenance installations.

Because this seal addresses the rear crankshaft interface, proper installation is critical to avoid oil leaks, ensure crankshaft end-play and maintain correct lubrication. PAI states this is a heavy-duty elastomer seal with reinforced sealing lip for exposure to crankcase oil and high temperatures. Before installation, users should confirm the rotation direction of the crankshaft (the spec states “Counter-Clockwise rear crankshaft rotation” for the listed family) and dimension match with the original.

Installation tip: Clean the crankshaft journal and seal housing thoroughly, inspect for wear or scoring, and apply the correct lubricant or break-in coating from the engine builder’s specification. If the old seal leaked, inspect the crankshaft snout, key-way and housing for wear before installing the new seal.