You don’t need to know which brake part failed to know something is wrong. Your trailer usually tells you, through the pedal, the brake controller or your nose. These are the signs we hear about most often at the shop, what usually causes each one, and when to stop towing.
The trailer pushes your truck
If you feel the trailer shoving the truck when you slow down, the trailer brakes aren’t doing their share. Common causes are brakes that are out of adjustment, a controller gain set too low, a broken wire to the brakes, or a surge actuator that isn’t working.
The brakes grab or lock up
Brakes that grab hard or lock a wheel can mean the controller gain is set too high. It can also point to grease on the brake shoes from a leaking hub seal, a bad magnet, or a sticking surge actuator. A locked trailer wheel is dangerous, so have it checked before your next tow.
The brakes feel weak, or do nothing
Weak brakes are often a matter of adjustment and worn shoes. On electric brakes, look at the magnets and wiring; on hydraulic brakes, check for low or leaking brake fluid.
Your controller shows a fault
Most controllers show a warning when they can’t see the trailer’s brakes, or when there’s a short. Start at the plug: check for corrosion and a loose or damaged blue brake wire. If the plug is fine, the fault is usually in the wiring along the frame or at a magnet.
You smell burning after towing
A hot, burning smell usually means a brake is dragging. Feel the hubs carefully after a short drive: one that’s much hotter than the others points to a sticking brake or a failing bearing. Both need attention before you tow again.
The trailer pulls to one side
If the trailer pulls left or right when you brake, one side is working harder than the other. The usual causes are a dead brake on one side, oil or grease on one set of shoes, or mismatched parts after a past repair.
Squealing or grinding
Squealing can be worn shoes. Grinding is more serious: it can mean metal on metal, or a magnet worn down to its backing. Stop and have it looked at.
Quick test
In an empty parking lot at walking speed, use the manual lever on your brake controller. The trailer should slow the whole rig noticeably without locking a wheel. If you feel nothing, don’t tow until it’s fixed.
How often to service trailer brakes
Brakes should be adjusted regularly, roughly every 3,000 miles, and inspected at least once a year. Boat trailers that go in salt water need checking more often, because rust and corrosion build up fast.
What we check in the shop
The controller signal at the plug
Wiring, connectors and grounds along the frame
Magnets, or wheel cylinders and calipers
Shoes, pads, drums and rotors
Hub seals and bearings, since a leaking seal ruins shoes
Adjustment on every wheel
Need a hand?
If you notice any of these signs, have the brakes checked before your next tow. We repair electric and hydraulic trailer brakes in our Port St. Lucie shop. Request a brake repair or call 772-924-7299.
General advice only. Check your trailer’s labels and manuals, or ask us before ordering or repairing.
