At a Glance
- >12" by 3-3/8" electric brake configuration
- >8,000 lb axle rating
- >4-bolt backing plate mount
- >Cast backing plate
- >Auto-adjusting brake design
- Brand: Rockwell
- SKU: 4739-R
Before You Order
Match the part number, measurements and connection points that apply to your trailer.
Fitment Check
| Hub Face | Measure hub face to hub face. |
|---|---|
| Spring Center | Measure mounting centers and confirm perch configuration. |
| Capacity | Match the required axle rating. |
| Brakes | Confirm brake type and flange configuration. |
Product Details
Right Hand - 12" by 3-3/8" Electric Trailer Brake – 8,000 lb – 4 Bolt Mount
Part Number: 4739-R
Right-hand (passenger side) 12" by 3-3/8" electric brake assembly for 8,000 lb trailer axles using a 4-bolt backing plate mount. Features a cast backing plate and auto-adjusting brake design. All internal brake components are pre-assembled on the backing plate for direct replacement.
R&P Knowledge Hub
This brake assembly is commonly used on imported 8K axles and is not used on standard Dexter 8,000 lb axles. It has been found on certain Quality Trailer, H&H, J&J, Lippert, and similar configurations.
Right-hand (RH) brake assemblies mount on the passenger side of the trailer axle. Always confirm brake size (12" by 3-3/8") and 4-bolt flange pattern before ordering.
Features
- 12" by 3-3/8" electric brake configuration
- 8,000 lb axle rating
- 4-bolt backing plate mount
- Cast backing plate
- Auto-adjusting brake design
- Pre-assembled for direct replacement
Specifications
| Specification | Detail |
|---|---|
| Brake Size | 12" by 3-3/8" |
| Axle Rating | 8,000 lb |
| Mounting Pattern | 4 Bolt |
| Orientation | Right Hand (Passenger Side) |
| Adjustment Type | Automatic |
Verify brake size, bolt pattern, and axle compatibility before installation.
Left Hand (Driver Side)
4739-L
4739-L
12" x 3.5" – 8K – 4 Bolt
Right Hand (Passenger Side)
4739-R
4739-R
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Pair – LH + RH
4739-L + 4739-R
4739-L + 4739-R
Complete set for one axle
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