Four Seasons 90786 HVAC Heater Core - Rear

Four Seasons 90786 Heater Core Overview

Four Seasons Heater Core 90786 is an aluminum HVAC heater core built for rear heating applications in select Mercury Villager and Nissan Quest models. It measures 5-7/8 inches long, 6-1/4 inches wide, and 1-7/8 inches thick, with an aluminum core construction that meets or exceeds OEM requirements.

The Four Seasons Heater Core line focuses on direct-fit replacement components for heating and cooling service. Part number 90786 is an aluminum heater core replacement for rear HVAC systems, including applications for 1993-2002 Mercury Villager and 1993-1998 Nissan Quest.

Key Features

• Aluminum heater core construction
• Dimensions: 5-7/8 in. length, 6-1/4 in. width, 1-7/8 in. thickness
• Meets or exceeds OEM specifications
• Rear HVAC heater core application
• Direct replacement for select Mercury Villager and Nissan Quest models
• Four Seasons part number 90786

Detailed Description

Four Seasons 90786 is an HVAC heater core designed for rear heating systems in compatible Mercury Villager and Nissan Quest vehicles. The aluminum core material supports efficient heat transfer and corrosion-resistant service characteristics commonly required in automotive HVAC repair. This heater core is listed for both aluminum design and copper/brass design applications within the covered vehicle range, making it a practical replacement choice when servicing the rear heater circuit on these vans.

This part cross-references Gates 2680 for the same application. It also aligns with other aftermarket references used for the same rear heater core fitment, including Spectra Premium 94786. Use Four Seasons 90786 when replacing a worn or leaking heater core in a 1993-2002 Mercury Villager rear HVAC system or a 1993-1998 Nissan Quest rear HVAC system.

What It Helps Fix

• Loss of cabin heat from a leaking or restricted heater core
• Coolant odor inside the vehicle from heater core seepage
• Fogging or film on interior glass caused by HVAC coolant leakage
• Uneven rear passenger heat output
• Reduced heater performance in Mercury Villager and Nissan Quest rear HVAC systems

Installation Notes and Tips

• Verify the vehicle year, make, model, and rear HVAC configuration before ordering.
• Confirm core dimensions and hose connection layout against the removed part.
• Inspect coolant condition and flush the system if contamination is present.
• Check related HVAC seals, hoses, and clamps during heater core service.
• Bleed the cooling system carefully after installation to remove trapped air.

Quality Assurance

Four Seasons 90786 is manufactured as an OEM-level replacement heater core and is specified to meet or exceed OEM requirements. It is built for direct replacement service in the listed rear HVAC applications.

Compatible Vehicles

• Fits 1999-2002 Mercury Villager, Rear
• Fits 1993-1998 Mercury Villager, Rear
• Fits 1993-1998 Nissan Quest, Rear