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Caterpillar · Hardware & Fasteners
3S9643
In stock · ships from Knoxville
This is a rotating shaft lip seal manufactured by Caterpillar, commonly used in engines to retain oil and keep out contaminants.
Confirm the part fits before you buy. Applications and interchange numbers are researched and audited per part.
We don't publish fitment for this part yet. Rather than guess, get it confirmed against your truck in under a minute.
Depending on the engine model, it may be installed as a crankshaft seal or thermostat housing seal. The seal is engineered for a shaft diameter of 2.272 inches (58 mm) and an outside diameter of 2.661 inches (67.6 mm). It is typically made from FKM or PTFE to handle high temperatures and rotational speeds. Replace this seal when oil leaks appear around the shaft or during an engine overhaul to avoid internal damage.
Part Number: 3S9643
SHAFT LIP SEAL
Vendor: STOWERS MACHINERY
Dealer: Knox Trailers
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