National 710551 Engine Crankshaft Seal - Front

Overview of National 710551 Engine Crankshaft Seal

The National 710551 engine crankshaft seal is designed to provide reliable sealing performance for various GM and Isuzu vehicles. Engineered with a PTFE material and a clockwise-spiral lip design, this oil seal helps maintain engine integrity by preventing oil leaks around the crankshaft.

• Inside diameter: 1.929 inches (49.000 mm)
• Outside diameter: 2.331 inches (59.200 mm)
• Thickness/width: 0.413 inches (10.500 mm)
• Material: Durable PTFE for enhanced wear resistance
• Helix type: Clockwise-spiral lip design for effective sealing
• Housing bore diameter: 2.323 inches (59.000 mm)
• Part number: 710551, Series 710500

Technical Details and Specifications

This National crankshaft seal (part number 710551) is constructed from PTFE, a material known for its chemical resistance and low friction properties, making it suitable for demanding engine environments. The seal features a clockwise-spiral lip design that ensures a tight fit around the crankshaft, reducing the risk of oil leakage. With an inside diameter of 1.929 inches and an outside diameter of 2.331 inches, it fits precisely into housings with a bore diameter of approximately 2.323 inches. The 0.413-inch thickness provides a robust barrier against contaminants while maintaining flexibility for installation.

Compatible Vehicles and Applications

This engine crankshaft seal is compatible with a range of vehicles including Buick, Chevrolet, GMC, Hummer, Isuzu, Oldsmobile, and Saab models. Specifically, it fits models such as the Chevrolet Colorado, Trailblazer, and Trailblazer EXT; GMC Canyon, Envoy, Envoy XL, Envoy XUV, H3, and H3T; Isuzu i-280, i-290, i-350, and i-370; Buick Rainier; Oldsmobile Bravada; Saab 9-7x; and Hummer Ascender.

Common Issues Addressed by the National 710551 Seal

• Prevents oil leaks around the engine crankshaft
• Reduces contamination ingress into the engine
• Maintains proper oil pressure and lubrication
• Minimizes wear on crankshaft and engine components
• Helps avoid costly engine repairs due to seal failure

Installation Notes and Tips

When installing the National 710551 crankshaft seal, ensure the housing bore is clean and free of debris. Use appropriate tools to press the seal evenly into place without damaging the PTFE lip. Verify the seal orientation matches the clockwise-spiral lip design for optimal sealing. Lubricate the seal lip lightly with engine oil before installation to reduce initial wear. Follow vehicle-specific service manual instructions for torque specifications and installation procedures.

Quality Assurance and Warranty

National engine seals are manufactured to meet OEM specifications and undergo rigorous quality control to ensure durability and performance. The 710551 seal is part of the 710500 series, known for consistent sealing reliability in automotive applications. While specific warranty details may vary, National typically offers coverage against manufacturing defects to provide confidence in product quality.