Dexter® Fortress Cap Service Kits

Shop genuine Dexter® Fortress cap service kits at Southwest Wheel® to reseal a Fortress aluminum oil cap without replacing the whole cap. These OEM kits restore leaking threaded and bolt-on Fortress caps with new O-rings or gaskets, oil fill plugs, Dexter logo rubber plugs, and bolt-on hardware where required. Kits cover Dexter, Lippert, AL-KO, and Rockwell oil hubs from 5,200 lbs. through 16,000 lbs.

Dexter® Fortress Cap Service Kits. Sold as kits that typically service two caps. Genuine Dexter® OEM Fortress oil-cap service parts.

Key Features

• Brand: Dexter® Axle
• Type: Fortress aluminum oil-cap service kits
• Cap Styles: Threaded Fortress caps and bolt-on Fortress caps
• Capacity Range: 5,200 lbs. to 16,000 lbs.
• Typical Contents: Dexter logo rubber plugs, oil fill plugs, and O-rings or bolt-on gaskets and bolts
• Applications: Dexter, Lippert, AL-KO, and Rockwell oil hubs using Fortress caps
• Construction: Genuine Dexter® OEM seals and plugs for a leak-free Fortress cap
• Use: Service a worn Fortress cap instead of replacing the aluminum cap body

Match the kit to the Fortress cap number stamped on the cap: 021-303-00, 021-302-00, 021-301-00, 021-305-00, 021-304-00, or bolt-on 021-259-00. These kits do not include the cap itself. After install, refill the hub with the oil Dexter specifies for that axle and check for leaks before towing.

Need help identifying a Fortress cap service kit? Call our trailer experts at 1-800-866-3336.

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