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Four Seasons 91545 HVAC Heater Core - view 1

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Four SeasonsPart #: 91545

Four Seasons 91545 HVAC Heater Core

Name: Four Seasons 91545 HVAC Heater Core
Brand: Four Seasons
SKU: BBRN-91545
Price: 84.75 USD
Availability: InStock

Heater Core

⚙️ 124 vehicles fit this part

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📦Heater Core

🚗Fitment: Buick, Chevrolet, Oldsmobile, and Pontiac, Century, Custom Cruiser, Cutlass, Cutlass Salon, Cutlass Supreme, El Camino, Grand Am, Grand LeMans, Grand Prix, GTO, LeMans, Malibu, Monte Carlo, and Regal

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Reliable Heater Core Replacement for Classic GM Vehicles

The Four Seasons Heater Core 91545 is designed to restore efficient heating performance in select Buick, Chevrolet, Oldsmobile, and Pontiac models. Engineered with durable copper and brass materials, this heater core ensures consistent heat transfer and long-lasting operation.

Core dimensions: 8 inches length, 7 inches width, 2 inches thickness
Constructed from copper/brass for enhanced thermal conductivity
Core depth and height precisely 2.000 and 8.000 inches respectively
Tube sizes: 0.625 inch (15.875 mm) and 0.750 inch (19.050 mm)
Meets or exceeds OEM specifications for reliable fit and function

Four Seasons Heater Core Product Line Overview

The Four Seasons Heater Core line focuses on delivering replacement cores that match or surpass original equipment standards. The Heater Core 91545 is part of this line, offering a copper/brass construction that provides durability and efficient heat transfer. This product line is tailored to meet the needs of various GM vehicles, ensuring compatibility and performance.

Detailed Product Description

This HVAC heater core is specifically designed for compatibility with Buick Century, Chevrolet Malibu, Oldsmobile Cutlass, Pontiac Grand Prix, and other classic GM models. The copper core material enhances heat transfer efficiency, while the brass components provide corrosion resistance. The fixed pipe positioning ensures a secure fit without the need for adjustments. With core dimensions of 8 inches by 7 inches by 2 inches, this heater core fits precisely within the HVAC system of the specified vehicles.

Common Applications and Issues Resolved

Restores heating performance in Buick Century and Chevrolet Monte Carlo
Replaces leaking or clogged heater cores in Oldsmobile Cutlass Supreme
Eliminates coolant odors inside Pontiac GTO and Grand Am cabins
Prevents engine overheating caused by faulty heater cores
Improves HVAC system efficiency in Chevrolet El Camino and Regal

Installation Notes and Tips

When installing the Four Seasons Heater Core 91545, ensure the vehicle is compatible by verifying make and model fitment. Drain the cooling system before removal to avoid spills. Handle the copper/brass core carefully to prevent damage to the tubes and fins. Since pipe positioning is fixed, confirm alignment with existing HVAC connections for a proper seal.

Quality Assurance and Warranty

This heater core meets or exceeds OEM standards, providing reliable performance and durability. Four Seasons products typically come with a limited warranty covering defects in materials and workmanship. Refer to the manufacturer’s warranty details for specific coverage information.

Brand	Four Seasons
Part Number	91545
Position	Heater Core
Length	8
Thickness	2
Width	7
Core Material	Copper
Adjustable Pipe Positioning	No
Core Depth IN	2.000
Core Height IN	8.000
Core Width IN	7.000
Description	Heater cores
Meets / Exceeds OEM?	Yes
Style	Copper/brass heater core
Tube 1 IN	0.625
Tube 1 MM	15.875
Tube 2 IN	0.750
Tube 2 MM	19.050
Type	Heater core /copper brass

This part fits 124 vehicles. Search below:

Year	Make	Model	Submodel	Body Type	Liters	Cylinders	Position	Notes
1977	Buick	Century		Wagon	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Buick	Century		Wagon	5.0L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Buick	Century		Wagon	3.8L	V6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Buick	Century		Wagon	6.6L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Buick	Regal		Sedan	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Buick	Regal		Coupe	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Buick	Regal		Sedan	5.0L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Buick	Regal		Coupe	5.0L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Buick	Regal		Sedan	3.8L	V6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Buick	Regal		Coupe	3.8L	V6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Chevrolet	El Camino					N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Chevrolet	Malibu					N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Chevrolet	Monte Carlo					N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Custom Cruiser					N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass	S		3.8L	V6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass	S		4.3L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass	S		5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass	S		6.6L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass	442		5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass	Colonnade		3.8L	V6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass	Colonnade		4.3L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass	Colonnade		5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass	Colonnade		6.6L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass	Colonnade S		3.8L	V6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass	Colonnade S		4.3L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass	Colonnade S		5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass	Colonnade S		6.6L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass Salon					N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Oldsmobile	Cutlass Supreme					N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Pontiac	Grand LeMans					N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Pontiac	Grand Prix					N/A	Compatible with models that do not have air conditioning.; Heater Core
1977	Pontiac	LeMans					N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Buick	Century		Wagon	3.8L	V6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Buick	Century		Wagon	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Buick	Regal		Sedan	3.8L	V6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Buick	Regal		Coupe	3.8L	V6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Buick	Regal		Sedan	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Buick	Regal		Coupe	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Chevrolet	El Camino					N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Chevrolet	Malibu					N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Chevrolet	Monte Carlo					N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Oldsmobile	Custom Cruiser					N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Oldsmobile	Cutlass	S		4.1L	L6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Oldsmobile	Cutlass	S		4.3L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Oldsmobile	Cutlass	S		5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Oldsmobile	Cutlass	S		7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Oldsmobile	Cutlass	Colonnade S		4.1L	L6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Oldsmobile	Cutlass	Colonnade S		4.3L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Oldsmobile	Cutlass	Colonnade S		5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Oldsmobile	Cutlass	Colonnade S		7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Oldsmobile	Cutlass Salon					N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Oldsmobile	Cutlass Supreme					N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Pontiac	Grand LeMans					N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Pontiac	Grand Prix					N/A	Compatible with models that do not have air conditioning.; Heater Core
1976	Pontiac	LeMans					N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Buick	Century		Wagon	3.8L	V6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Buick	Century		Wagon	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Buick	Regal		Sedan	3.8L	V6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Buick	Regal		Coupe	3.8L	V6	N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Buick	Regal		Sedan	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Buick	Regal		Coupe	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Chevrolet	El Camino					N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Chevrolet	Malibu					N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Chevrolet	Monte Carlo					N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Oldsmobile	Custom Cruiser					N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Oldsmobile	Cutlass					N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Oldsmobile	Cutlass Salon					N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Oldsmobile	Cutlass Supreme					N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Pontiac	Grand Am					N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Pontiac	Grand LeMans					N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Pontiac	Grand Prix					N/A	Compatible with models that do not have air conditioning.; Heater Core
1975	Pontiac	LeMans					N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Century		Sedan	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Century		Coupe	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Century		Convertible	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Century		Hardtop	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Century		Sedan	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Century		Coupe	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Century		Convertible	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Century		Hardtop	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Regal		Sedan	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Regal		Coupe	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Regal		Convertible	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Regal		Hardtop	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Regal		Sedan	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Regal		Coupe	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Regal		Convertible	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Buick	Regal		Hardtop	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Chevrolet	El Camino					N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Chevrolet	Malibu					N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Chevrolet	Monte Carlo					N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Oldsmobile	Custom Cruiser					N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Oldsmobile	Cutlass					N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Oldsmobile	Cutlass Supreme					N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Pontiac	Grand Am			6.6L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Pontiac	Grand Am			7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Pontiac	Grand Prix					N/A	Compatible with models that do not have air conditioning.; Heater Core
1974	Pontiac	LeMans					N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Century		Sedan	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Century		Coupe	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Century		Convertible	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Century		Hardtop	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Century		Sedan	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Century		Coupe	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Century		Convertible	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Century		Hardtop	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Regal		Sedan	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Regal		Coupe	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Regal		Convertible	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Regal		Hardtop	5.7L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Regal		Sedan	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Regal		Coupe	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Regal		Convertible	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Buick	Regal		Hardtop	7.5L	V8	N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Chevrolet	El Camino					N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Chevrolet	Malibu					N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Chevrolet	Monte Carlo					N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Oldsmobile	Custom Cruiser					N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Oldsmobile	Cutlass					N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Oldsmobile	Cutlass Supreme					N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Pontiac	Grand Am					N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Pontiac	Grand Prix					N/A	Compatible with models that do not have air conditioning.; Heater Core
1973	Pontiac	GTO					N/A	w/o AC; Heater Core
1973	Pontiac	LeMans					N/A	Compatible with models that do not have air conditioning.; Heater Core

* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.

This part directly replaces or is cross-referenced with the following part numbers:

181209822562501412791163024661399070554545660303270225670913182312729010070907090700915459454598545GM9070H2273HT399070ZH141

Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.