Park the trailer on firm and level ground.
Block the trailer tires on the opposite side securely so that no forward or rearward movement is possible.
Jack up the trailer following the manufacturers instructions.
Secure the trailer on jack stands of adequate capacity front and rear.
At the back of the wheel, on the brake backing plate, there is a small rubber plug near the bottom of the backing plate. Pry out this plug to give access to the star wheel adjuster.
Some trailers have a drop axle suspension system and the axle covers most of this adjusting hole making it difficult to use the brake tool. Patience will win out in the end if you keep at it.
Insert the brake adjuster tool and maneuver it so that the tool engages with the teeth in the star wheel. The star wheel looks like a gear with exposed teeth on the perimeter. On most trailers you would pull down on the tool handle which levers on the bottom of the hole and turns the star wheel up (as you are looking at it from the back of the wheel. Just to make it more difficult, the star wheel is located well inside and some maneuvering is required - a flashlight will help to locate the starwheel.
Turn the adjuster until the brake locks up, i.e. you can no longer rotate the wheel by hand. This centers the brake shoes on the brake drum so that they are in the correct position.
Now back off the star wheel 8 to 10 clicks or as specified by the manufacturer. The wheel should spin freely with no apparent drag to slow it down. A slight scraping noise is normal as the wheel turns.
Repeat this procedure for all the wheels.
Congratulations, you have successfully adjusted your own trailer brakes ... that wasn't so bad, was it?
Brakes worn out?
It can be more cost effective to replace the entire backing plate assembly than to replace the brake shoes alone. A new backing plate assembly will give you a new magnet as well and all new springs, etc. Also, they are easier to install ... simply remove the four bolts holding it on and disconnect two wires.
