National 320259 Engine Crankshaft Seal - Front

Overview of National Engine Crankshaft Seal 320259

The National 320259 engine crankshaft seal is designed for reliable sealing performance in select Buick, Chevrolet, Oldsmobile, and Pontiac vehicles. Engineered with precision, this oil seal helps maintain engine integrity by preventing oil leaks around the crankshaft.

• Inside diameter: 2.005 inches (50.930 mm)
• Outside diameter: 2.888 inches (73.360 mm)
• Thickness/width: 0.340 inches (8.640 mm)
• Material: durable fluoro-elastomer for heat and chemical resistance
• Clockwise-spiral helix lip design for effective sealing
• Compatible housing bore: 2.878 inches (73.100 mm)

Technical Details and Specifications

The National 320259 crankshaft seal features a fluoro-elastomer construction, providing resistance to high temperatures and engine fluids. Its clockwise-spiral lip design enhances sealing efficiency by directing oil back into the engine, reducing leakage. The seal fits shafts with a diameter of 2.005 inches and housing bores measuring approximately 2.878 inches, making it suitable for a range of GM vehicles. The 0.340-inch thickness ensures a secure fit and durability under engine operating conditions.

Compatible Vehicles and Applications

This engine crankshaft seal is compatible with various Buick, Chevrolet, Oldsmobile, and Pontiac models, including the Achieva, Alero, Calais, Cavalier, Cutlass Calais, Cutlass Supreme, Grand Am, Grand Prix, Malibu, Skylark, and Sunfire. It is specifically designed to replace worn or damaged seals in these vehicles, helping to maintain proper engine oil containment and prevent contamination.

• Prevents oil leaks around the crankshaft
• Reduces engine contamination from external debris
• Maintains engine oil pressure and performance
• Helps avoid costly engine repairs due to oil loss
• Addresses seal wear and damage from heat and friction

Installation Notes and Tips

When installing the National 320259 crankshaft seal, ensure the shaft and housing bore are clean and free of debris. Use appropriate tools to press the seal evenly into the housing bore without distortion. Verify the seal lip orientation matches the clockwise-spiral design for optimal sealing. Lubricate the seal lip lightly with clean 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 crankshaft seals are manufactured to meet industry standards for durability and performance. The fluoro-elastomer material and precision design contribute to long service life under normal operating conditions. This product is part of National's 320000 series, known for consistent quality in gaskets and sealing systems. Warranty coverage details should be confirmed with the product documentation or supplier.