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Cummins · Hardware & Fasteners
3963988
In stock · ships from Knoxville
The Cummins 3963988 is a genuine Cummins sealing washer used to create a leak-proof seal between mating surfaces on EPA13 6.7-liter ISB and QSB engines.
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Verified fitment for 4 applications
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It is typically installed in fuel, coolant, or lubrication system connections to prevent fluid or gas leaks. This washer should be replaced whenever the corresponding component is removed or if a leak is detected, to maintain engine efficiency and reliability.
Part Number: 3963988
SEALING WASHER
Dealer: KP Services Crossville
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