2-7/8"-12 Billet Aluminum Threaded Oil Cap Kit With O-Ring and Plug — 6K-8K Trailer Axle
Machined billet aluminum screw-in oil bath hub cap for compatible trailer hub and drum assemblies using a 2-7/8"-12 external thread.
Overview
This threaded oil bath hub cap is machined from solid billet aluminum and is designed to replace compatible screw-in oil bath caps that use a 2-7/8"-12 external thread. It is commonly used on oil-lubricated trailer hub and drum assemblies where a threaded cap is required.
R&P Service Insight
Oil bath caps should be matched by thread size, hub style, and lubrication system before installation.
- Threaded Fit: Designed for screw-in oil bath hub applications using a 2-7/8"-12 external thread.
- Oil Bath Use: Intended for oil-lubricated hub assemblies, not press-in grease cap applications.
- Fit Check: Compare the existing cap thread and hub style before ordering.
R&P Knowledge Hub
Compatibility: Commonly replaces oil bath caps similar to Dexter 21-35 where the thread size and hub configuration match.
Vehicle / System Fit: Designed for compatible oil bath trailer hub and drum assemblies.
Installation Notes: Verify 2-7/8"-12 thread size, screw-in cap style, and oil bath hub type before installation.
Performance Insight: Billet aluminum construction provides a durable machined cap option for compatible oil bath hub service.
Brand & Fitment Note
Selling Brand: R&P Carriages
Application Reference: Dexter and casting number references in this listing describe compatibility targets only where the thread size, hub style, and oil bath configuration match.
What This Means: This listing is for a billet aluminum threaded oil bath hub cap kit, not a guaranteed OEM-branded item unless specifically stated and verified.
Before Ordering: Verify thread size, hub type, lubrication system, cap style, and included sealing components before installation.
R&P Repair Insight
A leaking, damaged, cracked, or worn oil bath cap can allow lubricant loss or contamination. The most important ordering step is confirming that the hub uses a threaded oil bath cap, not a press-in grease or dust cap.
- Check the Thread: Confirm the existing cap uses a 2-7/8"-12 external screw-in thread.
- Check the Hub Type: Use only with oil bath hubs designed for threaded caps.
- Check the Application: Commonly used with oil bath drums carrying casting numbers such as 8-219, 8-232, 8-285, and 8-286 when the cap style and thread match.
Features
Threaded Oil Bath Design
Screw-in cap style for compatible oil-lubricated trailer hub assemblies.
Billet Aluminum Construction
Machined from solid billet aluminum for a durable replacement cap option.
2-7/8"-12 Thread Size
Designed for applications using a 2-7/8"-12 external thread.
Service Kit Presentation
Includes sealing components for installation as supplied with the kit.
Specifications
| Specification | Detail |
|---|---|
| Part Number | 21-35 Billet-Kit |
| Brand | R&P Carriages |
| Product Type | Threaded oil bath hub cap kit |
| Application | Oil-lubricated trailer hub assemblies |
| Material / Finish | Billet aluminum |
| Thread Type | External, screw-in |
| Thread Size | 2-7/8"-12 |
| Lubrication System | Oil bath hubs |
| Quantity | 1 hub cap kit |
Fitment / Application
| Category | Details |
|---|---|
| Vehicle / System | Trailer oil bath hub and drum assemblies |
| Primary Fit | Compatible screw-in oil bath hub caps using 2-7/8"-12 external thread |
| Common Reference | Commonly replaces oil bath caps similar to Dexter 21-35 where measurements and hub style match |
| Common Casting References | Often used on oil bath drums with casting numbers such as 8-219, 8-232, 8-285, and 8-286 when the cap style and thread match |
| Important Note | This is a threaded oil bath cap and is not compatible with press-in grease caps or dust caps. |
Included Components
| Quantity | Item |
|---|---|
| 1 | Billet aluminum threaded oil bath hub cap |
| 1 of each | Rubber O-Ring (046-032-00) and Rubber Plug (010-045-00) |
