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Cummins · Engine
3686406CUM
In stock · ships from Knoxville
This is a 12-volt solenoid valve for the engine compression brake (often called a Jake Brake) on Cummins ISX and QSX 15-liter diesel engines.
Confirm the part fits before you buy. Applications and interchange numbers are researched and audited per part.
Verified fitment for 8 applications
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All confirmed applications for this part number.
Other applications
Other applications
Primarily used on EPA13 (2013 and later) 15-liter ISX/QSX engines with the engine compression brake system. Always verify exact engine serial number and brake type to confirm fitment.
Part data verified against 5 catalog sources
Numbers this part supersedes or interchanges with. Showing 1 of 1.
Different year, make, or config? Get a confirmation against your truck in under a minute.
It controls oil flow to the engine brake mechanism, creating exhaust backpressure that helps slow the vehicle, reducing wear on service brakes. A failing solenoid can cause weak or inoperative engine braking, so replacing it restores full braking performance and safety on downgrades or when hauling heavy loads.
Part Number: 3686406CUM
JAKE BRAKE SOLENOID
Vendor: MHC Kenworth
Dealer: KP Services Crossville
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