National 40566S Wheel Seal - Front Inner

National 40566S Wheel Seal Overview

The National 40566S wheel seal is engineered to provide reliable sealing performance for driveline and axle applications. Designed with precision, this oil seal helps maintain proper lubrication and prevent contamination in compatible vehicle models.

• Inside diameter: 2.125 inches (53.980 mm)
• Outside diameter: 2.879 inches (73.130 mm)
• Housing bore: 2.875 inches (73.030 mm)
• Width: 0.250 inches (6.350 mm)
• Material: Durable nitrile rubber for resistance to oil and wear
• Type: 4s series oil seal

Detailed Product Description

The National 40566S wheel seal is part of the 40000 series, designed specifically for axle and driveline sealing systems. Constructed from nitrile material, it offers excellent resistance to oil, grease, and other automotive fluids, ensuring long-lasting performance. The seal’s precise dimensions, including a 2.125-inch inside diameter and 2.879-inch outside diameter, make it suitable for applications requiring tight sealing around shafts and housings. Its 0.250-inch width provides a compact yet effective barrier against contaminants.

Common Applications and Problem Solving

This wheel seal is commonly used in vehicles requiring reliable axle sealing solutions, including certain Ford and Chevrolet models. It addresses several common issues:

• Prevents oil leaks from axle assemblies
• Protects bearings from dirt and moisture intrusion
• Maintains lubrication integrity within the driveline
• Reduces wear on axle shafts by preventing contamination
• Helps avoid costly drivetrain repairs due to seal failure

Installation Notes and Tips

• Ensure the shaft and housing bore are clean and free of debris before installation
• Use appropriate tools to press the seal evenly into the housing bore to avoid damage
• Verify the seal orientation matches the vehicle manufacturer’s specifications
• Lubricate the seal lip lightly with compatible grease or oil prior to installation
• Inspect the seal for any defects before fitting to ensure proper sealing performance

Quality Assurance and Warranty

National wheel seals, including the 40566S, are manufactured to meet industry standards for durability and performance. Made from high-quality nitrile material, this seal is designed to withstand typical automotive operating conditions. While specific warranty details may vary, National products generally come with a limited warranty against manufacturing defects, providing confidence in the product’s reliability.