2 Pack - Billet Aluminum Oil Bath Dust Caps — 2-7/8"-12 Thread Pair
Durable billet aluminum oil bath dust cap pair designed to replace common clear plastic oil caps on compatible threaded trailer oil bath hubs.
Overview
This R&P Carriages aftermarket billet aluminum oil bath dust cap pair is a service-friendly replacement solution for compatible trailer oil bath hubs using 2-7/8"-12 threaded caps. Machined from solid aluminum, these caps offer a stronger alternative to common clear plastic oil caps while helping retain hub oil inside the assembly when properly installed with the included sealing components.
R&P Service Insight
Oil bath caps should be matched carefully to the hub thread and cap style before installation. A properly seated cap helps keep lubricant in the hub and contamination out.
- Thread Match: Confirm your hub uses 2-7/8"-12 threads before ordering.
- Seal Check: Inspect the O-rings and rubber center plugs during installation.
- Hub Maintenance: Verify oil level and hub condition before returning the trailer to road use.
R&P Knowledge Hub
Compatibility: Designed as an aftermarket replacement for Dexter 21-35 style oil caps using 2-7/8"-12 threads.
Vehicle / System Fit: Commonly used on trailer oil bath hubs found on many 7,000–9,000 lb trailer axle applications.
Installation Notes: Install with the included sealing components and verify that the cap seats properly before filling, checking, or operating the hub.
Performance Insight: Billet aluminum construction offers a more durable alternative to standard plastic oil caps in heavy-use trailer service.
Brand & Fitment Note
Selling Brand: R&P Carriages aftermarket replacement cap kit.
Replacement Reference: Dexter 21-35 oil cap style is used as a compatibility and replacement-reference term only.
What This Listing Includes: Two billet aluminum oil bath dust caps with rubber O-rings and rubber center plugs.
Before Ordering: Verify your existing cap thread size, hub type, oil bath cap style, and sealing surface before purchase.
R&P Repair Insight
Oil bath hub caps are small parts, but they play an important role in keeping lubricant inside the hub and contamination out. When replacing a cap, inspect the hub threads, O-ring contact area, and oil condition before returning the trailer to service.
- Check Threads: Damaged hub threads can prevent proper cap seating and sealing.
- Check Oil Level: Confirm proper hub oil level after cap installation.
- Check for Leaks: Inspect around the cap and plug after installation and again after initial use.
Features
Billet Aluminum Construction
Machined from solid aluminum for increased strength compared with common clear plastic oil bath caps.
Oil Bath Hub Design
Designed for compatible trailer oil bath hub systems where proper lubricant retention is critical.
Service-Friendly Pair
Includes two caps, making this a convenient pair-style replacement for trailer hub service.
Sealing Components Included
Kit includes rubber O-rings and rubber center plugs for proper cap installation.
Specifications
| Specification | Detail |
|---|---|
| Part Number | 21-35 Billet-Chrome-KITX2 |
| Listing SKU | 21-35 Billet-Chrome-KITX2 |
| Brand | R&P Carriages Aftermarket Replacement |
| Product Type | Oil Bath Dust Cap Pair |
| Quantity Included | 2 Caps / 1 Pair |
| Application | Trailer Oil Bath Hubs |
| Material / Finish | Billet Aluminum / Natural Aluminum Finish |
| Key Measurement | 2-7/8"-12 Thread |
| Cap Style | Threaded Oil Bath Dust Cap |
| Replacement Reference | Dexter 21-35 Oil Cap Style |
Fitment / Application
| Category | Details |
|---|---|
| Vehicle / System | Trailer Oil Bath Hub System |
| Primary Fit | Hubs requiring 2-7/8"-12 threaded oil bath caps |
| Secondary Fit | Commonly used on oil bath hubs for 7,000–9,000 lb trailer axle applications |
| Notes | May be associated with hub/drum casting references such as 8-219, 8-232, 8-285, and 8-286. Verify exact hub thread and cap style before ordering. |
Detailed Measurements
| Key Dimension | Measurement |
|---|---|
| Thread Size | 2-7/8"-12 |
| Replacement Reference | Dexter 21-35 Oil Cap Style |
| Cap Style | Threaded Oil Bath Dust Cap |
| Quantity | 2 Caps / 1 Pair |
Included Components
| Quantity | Item |
|---|---|
| 2 | Billet Aluminum Oil Bath Dust Caps |
| Included | Rubber O-rings |
| Included | Rubber Center Plugs |
