Gates 12318 HVAC Heater Hose - Heater Inlet

Gates Molded Heater Hose for Tight Engine Bays

The Gates Molded Heater Hose, part number 12318, is a factory-molded coolant hose built for compact engine compartments where a straight hose will not route correctly. It is made from EPDM and is specified for coolant, water, and air service, with marine application approval.

Compatible with Lexus RX350, RX350L, RX450h, and RX450hL heater inlet applications, this molded hose follows the OE-style shape needed for proper routing and fitment. The Gates 12318 is sized with 16 mm inside diameter ends and a 548 mm centerline length for the listed applications.

Key Features

• Factory-molded, OE-style heater hose design
• EPDM construction for coolant, water, and air service
• Small inside diameter profile for tighter engine compartments
• 16 mm inside diameter at both ends
• 548 mm centerline length
• Approved for marine applications
• Cross-reference part numbers include Carlson 13318 and OE-style references 872450E340 and F10576

Product Details

Gates Molded Heater Hose 12318 is engineered as a shaped replacement hose for heater inlet routing where exact bend geometry matters. The molded form helps maintain the correct path through the engine bay, while the EPDM material is suited for thermal and fluid exposure common in HVAC and cooling-system service. This part number is listed for 2016-2017 Lexus RX350, 2018 Lexus RX450h, 2018 Lexus RX450hL, and 2019-2022 Lexus RX350 and RX350L heater inlet locations.

What It Helps Address

• Cracked or hardened heater hose material
• Incorrect hose routing in tight engine compartments
• Coolant seepage at the heater inlet connection
• Restricted heater circuit flow caused by a deteriorated hose
• Fitment issues when a molded OE-style shape is required

Installation Notes

Verify the heater inlet routing, end diameters, and centerline length before installation. Compare the removed hose to the new Gates 12318 to confirm the molded shape matches the vehicle layout. Inspect adjoining clamps, fittings, and coolant condition during service, and refill and bleed the cooling system according to the vehicle manufacturer procedure after installation.

Quality Assurance

Gates supplies molded coolant hose products in OE-style configurations for modern vehicle packaging constraints. Part number 12318 is built to match the listed application dimensions and routing requirements for Lexus RX350, RX350L, RX450h, and RX450hL heater inlet service.