Mon–Fri 9:00 AM–5:00 PM CST  |  Sat 9:00 AM–3:00 PM  |  Sun Closed  |  Call or Text 815-357-3292  •  Free Shipping on Most Orders  •  Real-Time Rates When Applicable  •  Upgrade Delivery at Checkout  |  Ships Next Business Day Monday–Friday  |  We install what we sell — parts backed by real trailer service.  |  Need fitment help? Send us your trailer part photos and we will help you match it right.  |  How are we doing? Leave a review → Mon–Fri 9:00 AM–5:00 PM CST  |  Sat 9:00 AM–3:00 PM  |  Sun Closed  |  Call or Text 815-357-3292  •  Free Shipping on Most Orders  •  Real-Time Rates When Applicable  •  Upgrade Delivery at Checkout  |  Ships Next Business Day Monday–Friday  |  We install what we sell — parts backed by real trailer service.  |  Need fitment help? Send us your trailer part photos and we will help you match it right.  |  How are we doing? Leave a review →
FAMILY OWNED & OPERATED

12.25" x 4" Brake Back Plate Self Adjust Trailer Right Side 10000 Heavy Duty Cap (023-439-00)

$460.90
Most items ship free — select items ship for $6.39
Only 1 left
Not Sure It Fits? Ask a Pro
R & P Carriages

Dexter 12.25" x 4" 10,000 lb Nev-R-Adjust Electric Brake – RIGHT (Passenger Side)

Part Number: 023-439-00 | Dexter Ref: 23-439

One RIGHT (passenger side) 12-1/4" x 4" Dexter Nev-R-Adjust electric brake assembly for 10,000 lb heavy-duty trailer axles. Fully assembled and ready to mount to a 7-bolt brake flange. Designed for use with 12-1/4" electric brake drums commonly marked “9-27”.

Use Case – Tandem & Triple Axle Equipment Trailers

Used on high-capacity tandem and triple axle trailers requiring consistent electric braking across multiple axles. The self-adjusting mechanism maintains proper shoe-to-drum clearance and reduces manual adjustment during service intervals.

Use Case – Agricultural & Industrial Hauling

Commonly installed on agricultural and industrial trailers transporting heavy loads. The 12.25" x 4" shoe width provides increased braking surface area for higher load demands.

Specifications

Specification Details
Brake Type Electric Drum – Nev-R-Adjust
Drum Size 12.25" Diameter x 4" Wide
Axle Rating 10,000 lb Heavy Duty
Mounting Pattern 7-Bolt Flange
Side Right (Passenger Side)
Typical Drum Marking 9-27

R&P Knowledge Hub

Electric drum brake assemblies rely on proper orientation to function correctly. Left and right assemblies are not interchangeable due to internal actuation direction.

Always confirm drum diameter, shoe width, and flange bolt count prior to replacement. When servicing an axle, replace both sides as a matched left and right pair when possible.

Verify specifications before installation.

023-439-00 23-439 Dexter 10K electric brake right passenger side 12.25 x 4 7 bolt 9-27 drum Nev-R-Adjust heavy duty trailer
R & P Carriages Baseball Field Advertising Sign