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2 Pack - Billet Aluminum Oil Bath Dust Caps — 2-7/8"-12 Thread Pair (21-35 BILLET-CHROME-KITX2)

$99.13 $126.99
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At a Glance

  • SKU: 21-35 Billet-Chrome-KITX2
PRODUCT INFORMATION

Product Details

Oil Bath Hub Cap Replacement

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.

Part Number: 21-35 Billet-Chrome-KITX2 Pair / 2 Caps 2-7/8"-12 Thread

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
Verify thread size, hub type, cap style, O-ring condition, sealing surface, and oil bath hub compatibility before installation. Dexter 21-35 references are used for replacement-style identification only and do not mean this is a Dexter-branded part.
21-35 Billet-Chrome-KITX2 billet aluminum oil bath cap pair, 2-7/8-12 oil bath dust cap, Dexter 21-35 style replacement oil cap, trailer oil bath hub cap pair, billet aluminum trailer hub caps, oil bath dust caps with O-rings and plugs, replacement threaded oil bath caps, trailer axle oil cap pair, 7000 lb 8000 lb 9000 lb trailer hub oil cap application
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BEHIND THIS LISTING
PHOTOGRAPHY & RESEARCH Ariah Granados Ariah’s handwritten signature
DIGITAL PRESENTATION & DEVELOPMENT Ken Martin Ken’s handwritten signature
ONLINE SALES & QUALITY ASSURANCE Rayn Fisher
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