Four Seasons 90740 HVAC Heater Core

Four Seasons 90740 Heater Core

The Four Seasons 90740 heater core is an aluminum HVAC heater core built to match OE-style dimensions and performance requirements. It is made for direct replacement service in select Ford, Mercury, and Lincoln applications, including Crown Victoria, Grand Marquis, Marauder, and Town Car models.

Key Features

• Aluminum heater core construction for efficient heat transfer
• Core dimensions: 7-1/4 in. length, 6 in. width, and 1-7/8 in. thickness
• Core height: 7.250 in.; core width: 6.000 in.; core depth: 1.875 in.
• Tube size: 0.750 in. on both connections
• Meets or exceeds OEM requirements
• Four Seasons Heater Core line for HVAC repair and replacement

Detailed Description

Four Seasons 90740 is an aluminum heater core designed for HVAC systems that need reliable cabin heat and proper coolant-to-air heat exchange. Its OE-style sizing supports fitment in 1989-2011 Ford Crown Victoria, 1990-2011 Mercury Grand Marquis, 2003-2004 Mercury Marauder, and 1989-1997 Lincoln Town Car applications, along with related Ford and Mercury platform vehicles listed in the fitment data. The part number 90740 is also cross-referenced by Dorman - HELP 90740 for the same application.

This heater core is part of the Four Seasons Heater Core product line, focused on replacement HVAC core service with aluminum construction and factory-style dimensions. For 1989 Mercury Colony Park and 1989 Mercury Grand Marquis applications, swivel design pipes require rotation to match the original orientation. The part number 90740 is a direct-fit replacement choice for technicians servicing heater performance concerns on these full-size Ford and Mercury platforms.

Common Repair Uses

• Restores cabin heat when the original heater core is restricted or leaking
• Addresses coolant odor inside the vehicle caused by heater core failure
• Corrects weak or uneven heat output from the HVAC system
• Replaces a corroded or damaged aluminum heater core
• Supports repair of fogging or damp carpet conditions linked to heater core leaks

Installation Notes and Tips

Verify core dimensions, tube size, and pipe orientation before installation. This unit uses fixed pipe positioning, so confirm the inlet and outlet alignment against the original part. On 1989 Mercury Colony Park and 1989 Mercury Grand Marquis models, rotate the swivel design pipes to match the original orientation during installation. Always inspect the HVAC case, hoses, and coolant condition before completing the repair.

Quality Assurance

Four Seasons lists this heater core as meeting or exceeding OEM requirements, supporting replacement service where factory-style fit and function are needed. The aluminum construction and application-specific sizing help maintain consistent HVAC repair standards across the covered Ford, Mercury, and Lincoln vehicles.