Dorman 904-861 Vacuum Pump

Overview of the Dorman 904-861 Mechanical Vacuum Pump

The Dorman 904-861 vacuum pump is designed for reliable emission control in select GM vehicles. This mechanical vacuum pump is compatible with Cadillac Escalade, Chevrolet Silverado 1500, GMC Sierra, and other models, providing consistent vacuum pressure for optimal engine performance.

• Mechanical belt-driven vacuum pump with pulley included
• Cast aluminum housing for durability and heat resistance
• Includes gasket and mounting hardware for straightforward installation
• Single vacuum port with barbed connector for secure hose attachment
• Compatible with Cadillac Escalade, Chevrolet Silverado 1500, GMC Sierra, Yukon, and more

Detailed Product Features and Specifications

The Dorman 904-861 vacuum pump features a cast aluminum housing that ensures long-lasting durability and efficient heat dissipation. It operates via a belt drive system, with the included pulley facilitating smooth power transfer from the engine. The pump has one vacuum port with an outside diameter of 0.47 inches and an inside diameter of 0.215 inches, designed for a secure barbed connection. The outlet port measures 0.3 inches inside diameter and 0.355 inches outside diameter, optimized for proper vacuum flow. This mechanical pump does not include a relief valve or diaphragm but comes complete with all necessary mounting hardware and a gasket to ensure a proper seal during installation.

Compatible Vehicles and Applications

This vacuum pump is compatible with a range of GM trucks and SUVs, including:

• Cadillac Escalade and Escalade ESV
• Chevrolet Silverado 1500, 1500 LD, and 2500
• GMC Sierra, Sierra 1500, and Sierra 1500 Limited
• Chevrolet Tahoe
• GMC Yukon and Yukon XL
• Chevrolet and GMC Cheyenne models

Common Issues Addressed by the Dorman 904-861 Vacuum Pump

• Loss of vacuum pressure affecting brake booster performance
• Engine stalling or rough idle due to vacuum leaks
• Emission control system malfunctions related to vacuum supply
• Reduced fuel efficiency caused by improper vacuum operation
• Failure of vacuum-operated accessories in compatible GM trucks and SUVs

Installation Notes and Tips

Installation of the Dorman 904-861 vacuum pump is simplified by the inclusion of mounting hardware and a gasket. Ensure the belt drive system is properly tensioned and aligned to prevent premature wear. Verify that the vacuum hose fits securely on the barbed vacuum port to avoid leaks. It is recommended to inspect related vacuum lines and components during installation to maintain system integrity.

Quality Assurance and Warranty Information

Dorman vacuum pumps are manufactured to meet or exceed OEM specifications, using durable cast aluminum housings and quality components. The 904-861 part number is backed by Dorman's limited warranty, providing coverage against defects in materials and workmanship. This ensures dependable performance and peace of mind for your Cadillac, Chevrolet, or GMC vehicle.