Four Seasons 90045 HVAC Heater Core - Front

Four Seasons 90045 Heater Core Overview

The Four Seasons 90045 heater core is an aluminum HVAC heater core built for direct replacement in select Ford, Mercury, and Lincoln applications. It measures 7-1/2 inches long, 5-7/8 inches wide, and 1-7/8 inches thick, with 5/8-inch inlet and outlet tubes for a precise fit in the heater box.

Compatible with front HVAC locations on select 2002-2010 Ford Explorer, Ford Explorer Sport Trac, Mercury Mountaineer, Lincoln Aviator, and Ford Explorer Sport models, this heater core meets or exceeds OEM requirements and is part of the Four Seasons Heater Core line.

Key Features

• Four Seasons part number 90045
• Aluminum heater core construction
• Core dimensions: 7-1/2 in. x 5-7/8 in. x 1-7/8 in.
• 5/8-inch tube size on both connections
• Meets or exceeds OEM specifications
• Front HVAC application for select Ford, Mercury, and Lincoln vehicles

Product Details

The Four Seasons Heater Core product line focuses on replacement HVAC components built to match original equipment dimensions and connection points. Part number 90045 is an aluminum heater core with fixed pipe positioning and a compact core profile for the front heater assembly. This part cross-references Spectra Premium 93045 for the same application.

Fits 2007-2010 Ford Explorer, front; Fits 2007-2010 Ford Explorer Sport Trac, front; Fits 2007-2010 Mercury Mountaineer, front; Fits 2002-2006 Ford Explorer, front; Fits 2006 Mercury Mountaineer, front; Fits 2002-2004 Mercury Mountaineer, front; Fits 2003-2005 Lincoln Aviator, front; Fits 2002-2003 Ford Explorer Sport, front.

Common Heater Core Replacement Issues

• Loss of cabin heat
• Restricted coolant flow through the HVAC core
• Coolant odor inside the vehicle
• Fogging or film on the windshield from heater core leakage
• Uneven or weak defrost performance

Installation Notes

Verify core dimensions, tube size, and front-position fitment before installation. Confirm the vehicle’s year, make, and model against the listed applications for Ford Explorer, Mercury Mountaineer, Ford Explorer Sport Trac, Lincoln Aviator, and Ford Explorer Sport. Inspect the HVAC housing, coolant lines, and seals during replacement to ensure proper reassembly and leak-free operation.

Quality Assurance

Four Seasons lists this heater core as meeting or exceeding OEM specifications, supporting a direct-replacement standard for the listed applications. Part number 90045 is engineered for dimensional consistency and OE-style fit in compatible front HVAC systems.