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Mack · Cooling System
21037646
In stock · ships from Knoxville
This is a multi-purpose, Y-shaped coolant hose (commonly called a "cactus hose") for Mack E7 and ASET diesel engines.
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Verified fitment for 3 applications
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All confirmed applications for this part number.
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Other applications
Often listed as a lower thermostat hose or cactus hose. May be listed for various Mack truck models that use the E7 or ASET engine family.
Part data verified against 4 catalog sources
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It is typically installed at the lower thermostat housing and carries engine coolant between the block, thermostat, and radiator. Over time, this molded rubber hose can become brittle, swell, or develop cracks, leading to coolant leaks, so it is replaced during cooling system repairs or preventive maintenance.
Part Number: 21037646
MACK CACTUS HOSE
Vendor: McMahon Truck Center
Dealer: KP Services Crossville
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