RGP 10,000 lb Heavy-Duty Trailer Axle Electric Brake Assembly – 12-1/4" x 4", Self-Adjusting, 7-Bolt
RGP 10,000 lb Heavy-Duty Trailer Axle Electric Brake Assembly – 12-1/4" x 4", Self-Adjusting, 7-Bolt - Left Hand / Driver Side is backordered and will ship as soon as it is back in stock.
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Care information
Care information
To ensure optimal performance and extend the service life of your new trailer components, please follow these care guidelines after purchase:
- Before installation, check all parts for shipping damage or missing components. Do not install damaged parts.
- Always use correct tools and torque settings. Improper installation can lead to premature wear or failure.
- For bearings, suspensions, and brake components, apply high-quality trailer grease before first use if not pre-greased.
- Some parts (like brake assemblies) require a short break-in period to achieve full performance. Follow manufacturer instructions for best results.
- Recheck fasteners, grease levels, and moving components after 100 miles of towing, then at regular intervals.
- After exposure to water, road salt, or mud, clean and dry parts thoroughly. Apply anti-rust treatment if needed.
- If storing unused parts, keep them in a dry, sealed container away from moisture and direct sunlight.
Delivery and Shipping
Delivery and Shipping
Handling Time: Orders ship out within 1 business day after payment is received.
Shipping Methods: We use trusted carriers like UPS, FedEx, or USPS based on package size and destination.
Delivery Time: Estimated delivery within 2–6 business days (U.S. domestic orders).
Tracking: A tracking number will be provided once your order is dispatched.
Product Overview
Designed for 10,000 lb heavy-duty trailer axles, this electric brake assembly features a 12-1/4" x 4" brake size, forward self-adjusting operation, and a 7-bolt mounting configuration.
Available in left-hand and right-hand versions, this assembly is designed for compatible heavy-duty trailer braking systems and cross-references Dexter 023-438-00 and 023-439-00 applications. The self-adjusting mechanism helps maintain proper brake shoe clearance during normal operation, reducing the need for routine manual brake adjustments.
Select the correct brake position before ordering. Always verify axle capacity, brake dimensions, mounting flange pattern, and brake orientation to ensure proper fitment.
Specifications
Axle Capacity: 10,000 lb
Duty Rating: Heavy Duty
Brake Type: Electric Drum Brake
Adjustment Type: Forward Self-Adjusting
Brake Size: 12-1/4" x 4"
Brake Diameter: 12-1/4"
Brake Width: 4"
Mounting Flange: 7-Bolt
Available Positions: Left Hand / Right Hand
What’s Included
1× Electric Trailer Brake Assembly in the selected position
- Preassembled backing plate
- Brake shoes
- Electric brake magnet
- Springs and adjustment components
For a pair configuration:
1 × Left-Hand Brake Assembly + 1 × Right-Hand Brake Assembly
OEM / Replacement Reference
Left Hand / Driver Side
MAT: 77-1210HD-01
Dexter Cross Reference: 023-438-00
Dexter Kit Reference: K23-438-00
Right Hand / Passenger Side
MAT: 77-1210HD-02
Dexter Cross Reference: 023-439-00
Dexter Kit Reference: K23-439-00
Payment & Security
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