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Stemco 300-4009 Oil Cap 6 Bolt 5.5" Bolt Circle 021-038-02

In stock
SKU: 300-4009
Regular price $18.95

Stemco 300-4009 Oil Cap 6 bolt 5.5" bolt circle, Includes gasket and plug

Dexter Part Number 021-038-02

Same as 340-4009 Bulk Packaging

Fits Dexter Heavy Duty 22,500 to 27,500 Air Brake axles

Bolt Circle 5.5
Bolt Size 5/16
Number of Bolts 6
Overall Depth 2-11/16
Inside Depth 1-15/16
Flange Inner Diameter/Outer Dia 4-3/8-6-1/4
Plug Part Number 359-5990
Gasket Part Number 330-3009
Replacement Window Kit 359-5995


The traditional aluminum series provide durability with the trademark red plug to allow venting of the hub cap. Using cast aluminum for constructing the hub cap body prevents warpage and provides superior durability and heat-dissipation properties. The trucking industry recognizes STEMCO hub caps as the benchmark.


STEMCO® has provided the trucking industry with reliable hub caps for more than 60 years. Throughout our history, we have recognized the need for tougher, long-lasting hub caps that meet the performance, design and price requirements related to selecting the right hub cap for any fleet. To meet that need, STEMCO has engineered a menu of hub cap options designed to meet the varying performance expectations of each fleet, all in an effort to maximize performance and value.

  • Innovative Product Line Product- and application-specific technology designed to eliminate contaminants and extend wheel end life.
  • Superior Materials Cast aluminum to dissipate heat.
  • Numerous Lubricant Options Oil, semi-fluid grease, and hard-pack grease hub caps to meet performance, design and price requirements of today’s fleets worldwide.