Four Seasons 91548 HVAC Heater Core

Four Seasons 91548 Heater Core Overview

The Four Seasons 91548 heater core is a copper/brass HVAC heater core built to match the original-style cooling and cabin heat transfer layout used in select GM compact cars. With an 8-inch height, 5-1/2-inch width, and 2-inch depth, it is sized for direct replacement applications where dependable heater performance matters.

This Four Seasons Heater Core line focuses on OE-style fit and construction, and part number 91548 meets or exceeds OEM requirements for the listed applications.

Key Features

• Copper core material with copper/brass heater core construction
• Core dimensions: 8 in. height, 5-1/2 in. width, 2 in. depth
• Tube sizes: 0.625 in. and 0.750 in.
• Meets or exceeds OEM specifications
• Direct replacement HVAC heater core for listed Buick, Chevrolet, Oldsmobile, and Pontiac applications
• Four Seasons part number 91548

Detailed Description

Four Seasons 91548 is an HVAC heater core designed for vehicles equipped with the listed heating and air conditioning configurations. The copper/brass design supports efficient heat transfer through the heater system, helping restore proper cabin heat output in applications such as 1975-1980 Buick Skyhawk, 1975-1980 Chevrolet Monza, 1975-1980 Oldsmobile Starfire, and 1976-1980 Pontiac Sunbird. This part cross-references Spectra Premium 94550 for the same application.

For buyers searching for a heater core for 1975-1980 Buick Skyhawk with air conditioning, a heater core for 1975-1980 Chevrolet Monza with air conditioning, or a heater core for 1976-1980 Pontiac Sunbird without air conditioning, Four Seasons 91548 provides the specified OE-style replacement format.

What It Helps Fix

• Weak or uneven cabin heat
• Coolant odor inside the vehicle
• Fogging or film on the inside of the windshield caused by heater core leakage
• Visible coolant seepage from the HVAC heater core area
• Restricted heat transfer from a corroded or clogged heater core

Installation Notes and Tips

Verify the vehicle’s HVAC configuration before ordering, since fitment differs between air-conditioned and non-air-conditioned models in the listed applications. Confirm the tube sizes and core dimensions against the original unit before installation. Proper system flushing and leak inspection are recommended when replacing a heater core to help protect the new component and restore heater performance.

Quality Assurance

Four Seasons 91548 is listed as meeting or exceeding OEM requirements for the specified applications. The copper/brass construction and application-specific sizing support a direct replacement approach for the covered Buick, Chevrolet, Oldsmobile, and Pontiac models.