At Trademasters, we want to give you the knowledge and tools to keep your trailer in great shape for many years to come. As Chilliwack’s leading provider of high-end truck, trailer, and camper accessories, we have years of expertise to fall back on when clients approach us with unique challenges. In many cases, trailer problems can be avoided with routine servicing.

In today’s post, we’re going over why you should be scheduling regular services for your trailer’s undercarriage. Read on to learn more, and feel free to contact us if you have any questions regarding your trailer’s needs!

Problems With the Undercarriage Are Easily Missed

A very important and often overlooked aspect of trailer maintenance is the undercarriage. This includes a wide rage of components, including:

  • Axles
  • Brakes
  • Bearings
  • Suspension
  • Stabilizing jacks
  • Tongue jacks
  • RV batteries

If the battery is dead, or if the tongue jack is stripped, you’re probably going to notice. Problems with your axles, bearings, brakes, and suspension, however, are easily missed, since these components are behind the tires and rims. Often, an issue will go unnoticed until the wheels are removed, and small problems can turn into much more critical (and expensive) problems if they aren’t caught early on. This is why routine maintenance is crucial to the functionality and lifespan of your trailer.

Axles, Brakes, and Bearings

Most trailer brakes have drum brakes (disc brakes exist, but they are only found on high-end trailers and some boat trailers). We will focus here on electric drum brakes.

Let’s start with some background on drum brakes. Bolted on each end of the axle is a backing plate which has the brake shoes, adjusters, return springs, and magnets all as a complete unit. The hub drum is installed over top of the backing plate, the magnet, and the shoes. When you apply the brakes on the tow vehicle, an electric charge energizes the magnets, they grab onto the steel drum, and the rotation of the drum pulls the magnets forward, applying the brakes. When the brake pedal is released, the magnets de-energize and relax the tension on the brakes.

The bearings are another part of the inner workings of the axle. The bearings are installed inside the hub drum and slide over a polished steel spindle, supporting the weight of the trailer on the rims and tires. All of these components are serviceable parts.

Avoid Damage To Brakes and Bearings

One of the things that wears down your brakes and bearings is heat. There are many different sources from which this heat originates: the friction of the turning bearing, consistent braking, hot pavement, and more. Too much heat is bad for your brakes and bearings because:

  1. Heat can degrade the grease protecting the bearings
  2. Heat can crack the brake shoes

A dragging brake shoe or bad bearing can cause a lot of damage and be very expensive to repair. Brakes, like bearings, can be damaged by overheating which causes cracks on the shoe itself. If it falls apart while driving, the pieces can do internal damage to the drum.

What To Expect From A Brake and Bearing Service

During an axle service, or a brake and bearing service, a few different things happen. The tires are taken off and the hub drum is removed, exposing all of the components for the technician to inspect.

A typical brake and bearing service should happen every year (two years maximum) or after 10,000 — 15,000 km of driving. Most trailers don’t have an odometer to track distance, so it’s a good idea to review all the trips your RV takes in a year and add up the distance.

Proper axle grease will withstand the heat of driving, but like engine oil, it needs to be changed at regular intervals. During a bearing service, a technician will wash out the old grease, inspect the bearing, and, if the bearing doesn’t need changing, they will repack it with new grease. If the bearings are heat checked or pitted, they need to be replaced.

The suspension assembly is another serviceable component of the trailer and it can be done at the same time as a brake and bearing service. The suspension consists of the springs, equalizers, shackles, bolts, bushings, and if equipped, shocks. With the weight of the trailer and the torque produced on the suspension from turning, these parts will wear out over time.

How To Do A Brake and Bearing Safety Check

Make sure to do your safety checks while making scheduled stops for fuel or food during your travels. To do a safety check, walk to the trailer and put your hand on the rims — if possible, touch the center of the rim. It should feel warm to the touch, but if the center cap is so hot that you can’t touch it, that indicates a problem, and you should bring it in to be serviced.

Remember, always check the tires for full pressure and uneven wear before your trip too.

The Trademasters Team is Here To Help

If you have more questions about how to take care of your trailer, or if you’re looking for industry-leading camper accessories including trailer hitches, mud flaps, and more, feel free to contact us. The Trademasters team is proud to be Chilliwack’s chosen resource for truck, motorhome, and RV accessories!

Get in touch by sending us an email at, or give us a call at 604.792.3132. We look forward to speaking with you!