Gates 18623 HVAC Heater Hose - Throttle Body To Engine

Gates 18623 Molded Heater Hose Overview

Gates 18623 is a molded heater hose built for tight engine bays where a factory-shaped coolant line is needed. This EPDM hose is formed to follow the original routing and is used in coolant, water, and air applications, with marine approval noted by the manufacturer.

For Chevrolet Silverado, GMC Sierra, and related GM truck and SUV applications, Gates 18623 supports the throttle body to engine hose path with an OEM-style molded profile.

Key Features

• Factory-molded, OEM-style hose shape for compact engine compartments
• EPDM construction for heater and coolant service
• End I.D. of 6 mm (0.25 in) on both ends
• Centerline length of 122 mm (4.8 in)
• Used for coolant, water, and air applications
• Approved for marine applications
• Cross-references Dayco 86504 for the same application

Product Details

This Gates Molded Heater Hose line is built around precise formed routing rather than universal straight-hose fitment. Part number 18623 is a small I.D. molded coolant hose that matches the tighter packaging found in modern engine compartments. Its EPDM material and molded construction make it a direct-fit style service part for throttle body to engine routing on many GM platforms, including Chevrolet Avalanche, Silverado, Suburban, Tahoe, GMC Sierra, Yukon, and Cadillac Escalade applications listed below.

Compatible With 1999-2007 Chevrolet Silverado 1500, throttle body to engine; 2000-2006 Chevrolet Tahoe, throttle body to engine; and 1999-2007 GMC Sierra 1500, throttle body to engine. Gates 18623 is also listed for 2003-2007 Chevrolet Express vans and 2003-2007 GMC Savana vans in the same throttle body to engine position.

Common Problems This Hose Can Address

• Cracked or hardened molded heater hose material
• Coolant seepage at a throttle body to engine hose run
• Incorrect hose routing in a tight engine compartment
• Heat-related hose deformation or collapse
• Service replacement for a damaged OEM-style molded hose

Installation Notes and Tips

Verify the hose path, end diameters, and centerline length before installation. This part is listed for the throttle body to engine position, so match the original routing on the vehicle before replacing the hose. Confirm the application against the vehicle’s year, make, and model, especially on Chevrolet Silverado, GMC Sierra, and Cadillac Escalade platforms where multiple hose configurations may exist.

For best results, inspect adjoining fittings and clamps for wear, corrosion, or residue before installing the new hose. Gates 18623 should be installed on a clean, properly routed connection to maintain sealing and reduce stress on the molded shape.

Quality Assurance

Gates manufactures this hose as an OEM-style molded replacement using EPDM construction and application-specific shaping. The part is built to meet the dimensional and routing requirements called out in the product data for reliable service in coolant, water, air, and marine-use environments.