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

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R & P Carriages

Dexter FORTRESS 3.75" Aluminum Oil Caps – 10,000–16,000 lb Axles – Pair

Part Number: K21-304-00-PAIR

Genuine Dexter FORTRESS 3.75" diameter aluminum oil caps designed for 10,000–16,000 lb trailer axle applications. Engineered by Dexter for heavy-duty performance, these caps are built to meet demanding commercial and industrial trailer requirements.

Designed to fit select Dexter, Rockwell, Lippert, and AL-KO axle configurations. Always verify hub bore diameter before installation.

Kit Includes

Component Quantity
Dexter FORTRESS 3.75" Aluminum Oil Caps 2

Specifications

Specification Detail
Cap Diameter 3.75"
Material Aluminum
Axle Compatibility 10,000–16,000 lb
Manufacturer Dexter
Individual Part Number K21-304-00

Replaces

Brand Part Numbers
Dexter K71-859-00, K21-226-00, 021-229-00, 021-219-00, 021-12011
Valcrum ST-375
Rockwell 12001
AL-KO 568220, K568220

Important: Verify hub bore diameter and axle compatibility before installation.


K21-304-00-PAIR Dexter Fortress 3.75 aluminum oil cap 10000 lb 12000 lb 14000 lb 16000 lb axle replacement K71-859-00 ST-375 Rockwell 12001 AL-KO 568220