A fully assembled, bolt-on electric drum brake built for the driver-side (left hand) of trailers riding on 3500 lb rated axles. The automatic self-adjuster corrects shoe clearance on every stop, keeping your brake response consistent as linings wear -- no manual adjustments needed between service intervals.
The Lippert 296649 is engineered for RV trailers, utility trailers, and boat trailers running a 3500 lb axle. It ships as a complete, pre-assembled unit -- backing plate, shoes, linings, electromagnet, adjusting hardware, and springs are all included -- so you bolt it on and connect the two-wire harness rather than sourcing components individually.
The self-adjusting mechanism is the key difference over standard fixed-clearance brakes. Every time the trailer decelerates, the adjuster checks shoe-to-drum clearance and corrects it automatically. That means more consistent pedal feel, more even lining wear, and longer service life from both the shoes and the magnet.
Adjusts shoe clearance automatically on every stop. No manual star-wheel adjustments needed between routine servicing.
Arrives as a complete ready-to-install assembly -- backing plate, shoe and lining kit, magnet kit, adjuster screw, and all spring hardware included.
Specifically designed for the left side of the axle. Shoe geometry and adjuster direction are handed -- verify side before ordering.
Mounts to standard 4-bolt trailer axle flanges common across most 3500 lb straight and torsion axle hubs.
Note: A compatible brake drum is required and is NOT included. The mating hub/drum must be a 10-inch electric brake drum. A brake controller in the tow vehicle is also required for operation.
When the driver applies the tow vehicle brakes, the in-cab brake controller sends a proportional DC current through the trailer wiring harness to the brake magnet. The energized magnet is attracted to the rotating drum surface, which rotates the magnet arm and forces the primary shoe into the drum. The self-servo action then actuates the secondary shoe. The result is smooth, proportional stopping force that scales with controller output.
Because the shoes are self-adjusting, the clearance remains tight enough for responsive activation without dragging -- a common problem with manually adjusted brakes that go too long between service visits.
This assembly fits trailers equipped with 3500 lb rated axles and 10-inch electric brake drums. Common applications include:
This is the left hand (driver side) assembly. For the right hand (passenger side) counterpart, verify the matching Lippert part number before ordering -- shoe and adjuster geometry differ between sides.
The 296649 mounts to a standard 4-bolt axle flange. Installation steps at a high level: