National 710258 Engine Crankshaft Seal - Rear

Overview of National 710258 Engine Crankshaft Seal

The National 710258 engine crankshaft seal is designed to provide reliable sealing performance for various Chevrolet, GMC, and Hummer vehicles. Engineered with a fluoro-elastomer material and a counter-clockwise-spiral lip design, this oil seal ensures effective protection against oil leaks and contamination.

• Inside diameter: 115 mm (4.528 inches)
• Outside diameter: 135.2 mm (5.323 inches)
• Thickness/width: 10 mm (0.394 inches)
• Material: Durable fluoro-elastomer for high resistance to heat and chemicals
• Helix type: Counter-clockwise spiral lip design for enhanced sealing
• Compatible housing bore: 135 mm (5.315 inches)
• Part of the National 710200 series oil seals

Detailed Product Description

The National 710258 crankshaft seal is manufactured to meet the demanding requirements of engine sealing systems. Its fluoro-elastomer construction offers excellent resistance to engine oils, heat, and wear, making it suitable for heavy-duty applications. The counter-clockwise spiral lip design improves sealing efficiency by maintaining consistent contact with the crankshaft, reducing the risk of oil leakage. This seal is engineered to fit precisely within a 135 mm housing bore and accommodate a 115 mm shaft diameter, ensuring a secure and reliable fit.

Compatible Vehicles and Applications

This engine crankshaft seal is compatible with a range of Chevrolet, GMC, and Hummer models, including:

• Chevrolet Blazer, C1500, C1500 Suburban, C2500, C2500 Suburban, C3500, Express 2500, Express 3500, Tahoe, Yukon
• GMC C1500, C1500 Suburban, C2500, C2500 Suburban, C3500, Savana 2500, Savana 3500
• Hummer H1
• Additional models such as G20, G30, K1500, K1500 Suburban, K2500, K2500 Suburban, K3500, P30, P3500

Common Issues Addressed by the National 710258 Seal

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

Installation Notes and Tips

Proper installation of the National 710258 crankshaft seal is critical for optimal performance. Ensure the housing bore and crankshaft surfaces are clean and free of debris before installation. Use appropriate tools to press the seal evenly into the bore without damaging the sealing lip. Verify the seal orientation matches the counter-clockwise spiral lip design to maintain correct sealing direction. It is recommended to inspect the crankshaft for wear or damage prior to installation.

Quality Assurance and Warranty

National manufactures the 710258 crankshaft seal to meet industry standards for durability and performance. The fluoro-elastomer material and precision design contribute to a long service life under normal operating conditions. This product is part of the National 710200 series, known for consistent quality in engine sealing solutions. Warranty coverage details should be confirmed with the product documentation or manufacturer.