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21-88 Billet-KIT

3.5" BILLET ALUMINUM Oil Cap Fit Dexter 21-88 Trailer Axle bearing hub 10K 9-123 (21-88 Billet-KIT)

$50.66
Most items ship free — select items ship for $6.39
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R & P Carriages

Billet Aluminum 3.5" Oil Bath Cap – Replaces Dexter 21-88 – 10K Axle

Part Number: 21-88 Billet-KIT

Precision machined from solid billet aluminum, this heavy-duty 3.5" oil bath cap replaces the commonly broken clear plastic Dexter 21-88 oil caps found on 9,000 lb and 10,000 lb general duty axles.

Designed for durability and long-term performance, this cap provides a permanent solution for cracked or damaged factory oil caps while adding a clean, machined aluminum finish.

Features

  • Machined from solid billet aluminum
  • 3.5" thread outside diameter
  • 12-thread design
  • Includes new rubber O-ring and rubber fill plug
  • Practically indestructible compared to plastic caps
  • Clean machined aluminum appearance

Fitment & Compatibility

Axle Rating 9,000 lb – 10,000 lb General Duty
Replaces Dexter 21-88 Oil Cap
Drum Casting Numbers 8-415 (After July 2009)
Additional Drum Fitment 8-430 Hubs with 9-123 Drums (After April 2009)
Thread O.D. 3.5"