Four Seasons 90791 HVAC Heater Core - Front

Four Seasons 90791 Heater Core

The Four Seasons 90791 heater core is an aluminum HVAC heater core built to match the listed Toyota 4Runner applications. It is specified with a 8-5/8 in. core height, 6-1/2 in. core width, and 1-1/4 in. core depth for a direct-fit replacement in front HVAC systems.

Four Seasons Heater Core line parts are focused on replacement HVAC components for vehicles that need accurate fitment and OE-style dimensions. This aluminum heater core meets or exceeds OEM requirements and uses 0.625 in. inlet/outlet tube sizing for the listed applications.

Key Features

• Part number 90791 heater core for Toyota 4Runner HVAC repair
• Aluminum core material with aluminum heater core construction
• Core dimensions: 8-5/8 in. height, 6-1/2 in. width, 1-1/4 in. depth
• 0.625 in. tube size on both connections
• Meets or exceeds OEM specifications
• Front-position HVAC heater core application

Detailed Description

This Four Seasons heater core is a direct replacement HVAC component for select Toyota 4Runner models with front heater core applications. It is listed for 1984-1988 Toyota 4Runner front applications without rear A/C in both aluminum design and copper/brass design configurations, 1989-1995 Toyota 4Runner front applications in aluminum design and copper/brass design configurations, and 1996 Toyota 4Runner front applications through 11/95 for both aluminum design and copper/brass design versions. The 90791 heater core is built with aluminum core material and dimensions that support proper fitment in the factory HVAC case.

This part cross-references APDI 9010006 for the same application.

What It Helps Address

• Loss of cabin heat from a leaking or restricted heater core
• Coolant odor inside the vehicle from heater core seepage
• Fogging or film on the windshield caused by HVAC coolant leakage
• Uneven or weak heat output from the front HVAC system
• Replacement needs during Toyota 4Runner heater core service

Installation Notes and Tips

Verify the vehicle’s heater core design before ordering, since the listed fitment includes aluminum and copper/brass configurations. Confirm the front HVAC application, core dimensions, and 0.625 in. tube sizing against the original part before installation. Access to the heater core typically requires removal of HVAC components, so inspect hoses, seals, and coolant condition during service.

Quality Assurance

This Four Seasons 90791 heater core is listed as meeting or exceeding OEM specifications for the applications shown. Use the fitment details to confirm the correct Toyota 4Runner configuration before installation.