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Dexter FORTRESS 3.75" Diameter Aluminum Oil Cap for 10,000-16,000 lb axles (K21-304-00)

$48.28
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R & P Carriages

Dexter FORTRESS Aluminum Oil Bath Hub Cap — 3.75" Diameter

Part Number: K21-304-00

Genuine Dexter FORTRESS series aluminum oil bath hub cap designed for use on heavy-duty oil-lubricated trailer hubs. This cap features a 3.75" diameter and is intended for select 10,000 lb through 16,000 lb axle applications. Engineered by Dexter for compatibility with specific hub and spindle systems.

Features

  • Genuine Dexter FORTRESS series oil bath hub cap
  • Machined aluminum construction
  • Designed for oil-lubricated trailer hubs
  • 3.75" diameter cap size
  • Direct replacement style component for select heavy-duty axles

Specifications

Specification Detail
Manufacturer Dexter
Series FORTRESS
Part Number K21-304-00
Hub Type Oil bath
Cap Diameter 3.75"
Axle Rating Range Typically used on 10K–16K axle systems
Material Aluminum

This cap replaces several legacy oil cap designs used across multiple axle platforms. Verify hub bore size, spindle nut clearance, and manufacturer specifications before installation.

oil bath hub cap, heavy duty trailer hub, axle oil cap replacement, trailer hub components