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Dexter 10KHD 12K 15K Trailer Axle 4" 2PC Threaded Oil Bath Cap


Regular price $32.99
Shipping calculated at checkout.

Care information

To ensure optimal performance and extend the service life of your new trailer components, please follow these care guidelines after purchase:

  • Before installation, check all parts for shipping damage or missing components. Do not install damaged parts.
  • Always use correct tools and torque settings. Improper installation can lead to premature wear or failure.
  • For bearings, suspensions, and brake components, apply high-quality trailer grease before first use if not pre-greased.
  • Some parts (like brake assemblies) require a short break-in period to achieve full performance. Follow manufacturer instructions for best results.
  • Recheck fasteners, grease levels, and moving components after 100 miles of towing, then at regular intervals.
  • After exposure to water, road salt, or mud, clean and dry parts thoroughly. Apply anti-rust treatment if needed.
  • If storing unused parts, keep them in a dry, sealed container away from moisture and direct sunlight.

Delivery and Shipping

Handling Time: Orders ship out within 1 business day after payment is received.

Shipping Methods: We use trusted carriers like UPS, FedEx, or USPS based on package size and destination.

Delivery Time: Estimated delivery within 2–6 business days (U.S. domestic orders).

Tracking: A tracking number will be provided once your order is dispatched.

Upgrade your heavy-duty trailer with this premium 4" oil bath cap kit from Trailer Supplies, designed to replace Dexter part number 21-36. Engineered for 10K (HD), 12K, and 15K trailer axles, this aftermarket cap features a durable threaded design with a 4-inch outer diameter and 12 threads per inch. The kit includes a rubber plug and O-ring to ensure a tight, leak-free seal that keeps your hub properly lubricated. Please note: this cap is not compatible with Dexter’s 10K General Duty axles made in 2009 or later (#21-88). Always verify your thread size before ordering to ensure proper fit.

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