Genuine Dexter 12-1/4" Electric Trailer Brake Magnet Kit
Genuine Dexter replacement magnet kit for compatible Dexter 12-1/4-inch electric trailer brakes rated from 7,200 through 15,000 lbs. and manufactured after June 1992. (Replaces K71-441-00 K71-375-00 K71-376-00 and K71-377-00)
Key Measurements & Specs
| Specification | Detail |
|---|---|
| Manufacturer Part Number | K71-378-00 |
| Brand | Dexter |
| Product Type | Electric trailer brake magnet replacement kit |
| Brake Diameter | 12-1/4 inches |
| Brake Type | Electric drum brake |
| Axle Capacity Range | 7,200–15,000 lbs. |
| Production Date Fit | Compatible brakes manufactured after June 1992 |
| Quantity Included | 1 magnet replacement kit |
Fitment / Application
| Category | Details |
|---|---|
| Manufacturer | Dexter axles and brake assemblies only |
| Brake Size | Compatible Dexter 12-1/4" electric brakes |
| Axle Ratings | 7.2K, 8K, 9K, 10K, 10K HD, 12K and 15K applications where Dexter specifies K71-378-00 |
| Brake Side | Suitable for compatible left-hand or right-hand brake assemblies |
| Production Requirement | Brake must have been manufactured after June 1992 |
| Fitment Method | Confirm the Dexter brake manufacturer, 12-1/4" brake diameter, production date and axle/brake identification before ordering |
| Important Note | Wire color alone should not be used to identify brake capacity or fitment |
Top Features
| Feature | Buyer Benefit |
|---|---|
| Genuine Dexter Kit | Provides a manufacturer-specified replacement for compatible Dexter brake applications |
| Broad Heavy-Duty Fit | Covers compatible Dexter 12-1/4" electric brakes from 7.2K through 15K |
| Complete Service Kit | Includes the magnet assembly, mounting spring and retaining clip |
| Updated Magnet Assembly | Uses Dexter’s current replacement magnet assembly for multiple earlier wire-color applications |
Important Fitment Note: Fits compatible Dexter 12-1/4-inch electric brakes manufactured after June 1992. Do not determine compatibility from wire color alone. Confirm the Dexter brake application, brake dimensions, axle capacity and production date before ordering. This kit services one brake assembly; order the required quantity for the number of brakes being repaired.
R&P Service Insight
A trailer brake magnet should be matched to the brake assembly—not selected by appearance or wire color alone. Dexter has consolidated several earlier magnet applications into this current replacement kit.
- Confirm the brand: This kit is specifically intended for compatible Dexter electric brakes.
- Confirm the brake size: The brake assembly must use a 12-1/4-inch brake configuration.
- Inspect related parts: Check the brake drum surface, shoes, wiring and mechanical hardware while the brake is open.
R&P Knowledge Hub
Compatibility: Dexter identifies K71-378-00 for compatible 12-1/4-inch electric brakes in the 7.2K–15K range manufactured after June 1992.
Brake-System Fit: The kit services one compatible left-hand or right-hand Dexter electric drum brake assembly.
Installation Notes: Disconnect trailer power before brake service. Route the new magnet wires so they remain clear of moving brake hardware and cannot rub against the drum.
Performance Insight: When energized by the trailer brake controller, the magnet contacts the rotating drum surface and moves the brake actuating mechanism. Proper magnet condition and drum contact are necessary for consistent electric-brake operation.
R&P Repair Insight
If one wheel has weak or inconsistent braking, inspect the entire brake circuit before assuming the magnet is the only problem. Damaged wiring, poor grounds, worn drum surfaces, contaminated brake shoes and incorrectly adjusted brakes can produce similar symptoms.
- Magnet Face: Inspect the magnet’s contact face for abnormal wear, deep grooves or physical damage.
- Drum Surface: Check the armature surface inside the brake drum for scoring, uneven wear or contamination.
- Electrical Circuit: Inspect the brake wiring and connections for corrosion, broken conductors, poor splices or damaged insulation.
Features
Genuine Dexter Component
Manufacturer-specified replacement kit for compatible Dexter 12-1/4-inch electric trailer brakes.
Heavy-Duty Brake Compatibility
Fits applicable Dexter brake configurations ranging from 7,200 through 15,000 lb. axle capacities.
Spring and Retainer Included
Includes the dedicated mounting spring and retaining clip needed to secure the replacement magnet.
Services One Brake
One kit contains the components required to replace the magnet in one compatible brake assembly.
Included Components
| Quantity | Item | Dexter Part Number |
|---|---|---|
| 1 | Brake magnet assembly | 042-131-00 |
| 1 | Magnet mounting spring | 046-117-00 |
| 1 | Magnet retaining clip | 027-050-00 |
