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" |