Dorman 603-103 Engine Coolant Reservoir - Front

Reliable Engine Coolant Reservoir for Buick, Cadillac, Oldsmobile, Pontiac

The Dorman 603-103 engine coolant reservoir is designed to provide a durable and precise fit for select Buick, Cadillac, Oldsmobile, and Pontiac models. Constructed from high-quality plastic, this reservoir ensures proper coolant storage and system performance.

• Material: Durable plastic construction for long-lasting use
• Dimensions: Length 242 mm, Height 262 mm for accurate fitment
• Color: White reservoir body for easy coolant level monitoring
• Mounting: Includes mounting brackets and two mounting holes for secure installation
• Cap: Comes with a compatible cap, non-pressurized design
• Package Contents: One coolant reservoir and one cap included

Product Details and Specifications

The Dorman 603-103 engine coolant reservoir is engineered to meet the specifications required by various GM vehicles, including Buick LeSabre, Cadillac DeVille, Oldsmobile 88 and 98, Pontiac Bonneville, and others. Its plastic construction resists corrosion and withstands engine bay conditions. The reservoir measures 242 mm in length and 262 mm in height, ensuring a proper fit within the engine compartment. The white color allows for easy visual inspection of coolant levels. This reservoir includes mounting brackets and two mounting holes for a secure and stable installation. The included cap is designed for non-pressurized systems, maintaining proper coolant containment without pressure buildup.

Compatible Vehicles and Applications

This engine coolant reservoir is compatible with the following makes and models:

• Buick LeSabre, Park Avenue, and LSS
• Cadillac DeVille, Fleetwood
• Oldsmobile 88, 98
• Pontiac Bonneville, Grand Prix, and Regency

Use this reservoir to replace worn or damaged coolant tanks in these vehicles, ensuring proper coolant circulation and engine temperature regulation.

Common Issues Addressed by This Coolant Reservoir

• Coolant leaks due to cracked or damaged reservoir tanks
• Inaccurate coolant level readings from discolored or opaque reservoirs
• Loose or missing mounting brackets causing reservoir movement
• Faulty or missing reservoir caps leading to coolant evaporation
• Overheating issues related to improper coolant containment

Installation Notes and Tips

Installation of the Dorman 603-103 reservoir requires removal of the old coolant tank and careful alignment of the mounting holes. Use the included mounting brackets to secure the reservoir firmly in place. Ensure the cap is properly seated to prevent coolant leaks. Since mounting hardware is not included, retain or reuse existing fasteners if possible. Always allow the engine to cool before beginning installation to avoid injury from hot coolant.

Quality Assurance and Warranty

Dorman parts are manufactured to meet or exceed OEM standards for fit, form, and function. The 603-103 engine coolant reservoir undergoes quality checks to ensure durability and reliability. While specific warranty details may vary, Dorman typically offers a limited warranty covering defects in material and workmanship. Refer to Dorman’s official warranty policy for complete information.