Dayco 88445 Engine Coolant Bypass Hose

Dayco 88445 Small I.D. Heater Hose Overview

Dayco 88445 is an engine coolant bypass hose built for applications that require a dual inside diameter connection. Made from EPDM and finished in black, it provides a direct-fit cooling system hose solution for select Chevrolet and GMC trucks and vans, including Silverado 2500 HD, Silverado 3500, Sierra 2500 HD, Sierra 3500, and related models.

The Dayco Small I.D. Heater Hose line focuses on replacement hoses for tight-radius coolant routing and smaller heater or bypass connections. Part number 88445 follows SAE J20R3 Class D-1 and SAE J1684 Type EC specifications for the listed applications.

Key Features

• Part number: 88445
• Engine coolant bypass hose / small I.D. heater hose application
• Dual I.D. hose with 7/8 in. end 1 inside diameter and 1 in. end 2 inside diameter
• EPDM construction for cooling system service
• Black finish
• SAE J20R3 Class D-1 and SAE J1684 Type EC specification reference
• No heat shield and no protective sleeve
• Cross-reference: ACDelco 14367S

Detailed Description

Dayco 88445 is a dual I.D. engine coolant bypass hose engineered for cooling system routing where one end measures 7/8 inch inside diameter and the other measures 1 inch inside diameter. The EPDM hose construction is suited to coolant transfer in the heater and bypass circuit, while the black exterior provides a clean OE-style appearance. This hose is listed for 2001-2007 Chevrolet and GMC applications, including 2001-2006 Chevrolet Silverado 2500 HD, 2001-2006 Chevrolet Silverado 3500, 2001-2006 GMC Sierra 2500 HD, 2001-2006 GMC Sierra 3500, and 2007 Chevrolet Silverado 2500 HD Classic and GMC Sierra 3500 Classic.

For buyers searching for a Dayco 88445 heater hose, a small I.D. heater hose for Chevrolet Silverado 2500 HD, or an engine coolant bypass hose for GMC Sierra 3500, this part number matches the listed fitment and SAE specifications. It also cross-references ACDelco 14367S for the same application.

Vehicle Fitment

• Fits 2007 Chevrolet Silverado 2500 HD Classic, N/A
• Fits 2007 Chevrolet Silverado 3500 Classic, N/A
• Fits 2007 GMC Sierra 2500 HD Classic, N/A
• Fits 2007 GMC Sierra 3500 Classic, N/A
• Fits 2002-2006 Chevrolet Avalanche 2500, N/A
• Fits 2001-2006 Chevrolet Silverado 2500 HD, N/A
• Fits 2001-2006 Chevrolet Silverado 3500, N/A
• Fits 2001-2006 Chevrolet Suburban 2500, N/A
• Fits 2001-2006 GMC Sierra 2500 HD, N/A
• Fits 2001-2006 GMC Sierra 3500, N/A
• Fits 2001-2006 GMC Yukon XL 2500, N/A
• Fits 2001-2002 Chevrolet Express 3500, N/A
• Fits 2001-2002 GMC Savana 3500, N/A

Common Replacement Uses

• Replacing a cracked or softened coolant bypass hose
• Restoring heater circuit coolant flow on listed Chevrolet and GMC vehicles
• Addressing coolant seepage at a dual-diameter hose connection
• Replacing a worn small I.D. heater hose during cooling system service
• Correcting hose fitment issues on Silverado, Sierra, Suburban, Express, and Savana applications

Installation Notes and Tips

Verify both hose-end inside diameters before installation: 7/8 inch on one end and 1 inch on the other. Confirm routing against the original hose path and inspect adjoining clamps, fittings, and coolant connections for wear before installing Dayco 88445. Because this hose does not include a heat shield or protective sleeve, keep it routed away from sharp edges and high-heat contact points.

Quality Assurance

Dayco manufactures cooling system hoses to published SAE specifications for the listed applications. Part number 88445 is built as an EPDM replacement hose for the specified Chevrolet and GMC fitments.