National 221510 Transfer Case Shift Shaft Seal

Overview of National Transfer Case Shift Shaft Seal 221510

The National Transfer Case Shift Shaft Seal 221510 is engineered to provide reliable sealing performance for transfer cases in select Chevrolet, Geo, Lexus, and Toyota vehicles. Designed with precision dimensions and durable polyacrylate material, this oil seal helps maintain proper fluid retention and prevents contamination in the transfer case assembly.

• Inside diameter: 0.591 inch (15.000 mm)
• Outside diameter: 0.994 inch (25.250 mm)
• Thickness/width: 0.236 inch (6.000 mm)
• Sealing material: Polyacrylate for enhanced durability
• Compatible with housing bore size: 0.984 inch (25.000 mm)
• Part number: 221510

Detailed Product Description and Specifications

This National transfer case shift shaft seal (part number 221510) is manufactured from polyacrylate, a material known for its resistance to heat, oil, and wear. The seal features an inside diameter of 0.591 inch (15 mm) and an outside diameter of 0.994 inch (25.25 mm), with a thickness of 0.236 inch (6 mm). These precise measurements ensure a secure fit within the transfer case housing bore of 0.984 inch (25 mm), providing an effective barrier against oil leaks and external contaminants.

Compatible with a range of vehicles including Chevrolet Nova, Pickup, and Prizm; Geo Prizm and Paseo; Lexus GX460, GX470, and RX models; and Toyota 4Runner, Camry, Celica, Corolla, FJ Cruiser, MR2, Sequoia, T100, Tacoma, Tercel, and Tundra, this seal supports proper transfer case operation across multiple platforms.

Common Applications and Problem Resolution

• Prevents oil leaks from the transfer case shift shaft
• Reduces contamination ingress that can cause premature wear
• Maintains transfer case fluid integrity for smooth shifting
• Addresses seal degradation due to heat and friction
• Helps avoid costly transfer case repairs related to fluid loss

Installation Notes and Tips

• Ensure the transfer case housing bore is clean and free of debris before installation
• Verify the shaft diameter matches the seal’s inside diameter (0.591 inch / 15 mm)
• Use appropriate tools to press the seal evenly into the housing bore without distortion
• Inspect the seal lip for damage prior to installation to ensure proper sealing
• Follow vehicle-specific service manual instructions for transfer case disassembly and reassembly

Quality Assurance and Warranty Information

National’s transfer case shift shaft seal 221510 is manufactured to meet industry standards for durability and performance. The polyacrylate material offers resistance to oil, heat, and wear, contributing to a longer service life. While specific warranty details may vary, National typically provides coverage against manufacturing defects to ensure customer confidence in the product’s reliability.