A Comprehensive Guide to Trailer Maintenance

Keeping your trailer in tip-top shape is not only a matter of avoiding costly repairs but also of keeping you and others safe and making sure you can use your trailer for years to come.

This guide will walk you through everything you need to know about trailer maintenance, from the roof to the wheels, blinkers to ball mount. While every trailer is a little different, this should give you a good idea of where to start!

1. The Importance of Routine Trailer Maintenance 
2. Pre-Tow Inspection Checklist 
3. Essential Trailer Maintenance Tasks 
4. Seasonal Trailer Maintenance Tips 

Plus, don't forget to download our handy trailer maintenance checklist PDF for free!

As tedious as trailer service and maintenance may seem, its importance cannot be doubted. Trailers, like any piece of equipment, need regular care to work safely and efficiently.

The most vital thing routine maintenance provides is safety. Your trailer needs to be in one fully functioning piece before you hit the road for a variety of reasons. Worn-down tires can burst and roughen your ride (or stop it entirely). Malfunctioning lights will confuse the vehicles around you. Worn-down brakes can make it hard for you to stop or go. If your hitching system breaks and your trailer gets away from you on the road, it could seriously threaten both your equipment and your surroundings. Trailer servicing and maintenance can help you catch problems before they become disasters!

Longevity is another gift trailer maintenance can provide. Much like how going to the doctor regularly can help you live better and longer, regular maintenance extends the life of your trailer by fixing small problems and preventing bigger issues. For example, if you replace a damaged tire, you won’t have to deal with the fallout of a blowout!

Routine trailer care and maintenance also allows your trailer to run more smoothly, which means less wear-and-tear on its components and a longer lifetime for the trailer as a whole.

Even your wallet benefits from regular trailer maintenance. While maintenance requires time and sometimes a little money, it costs a lot less than repairing damage from an accident or replacing trailer parts you could have prolonged the use of. If you ever want to sell your trailer, routine maintenance helps with that too! A well-maintained trailer has a far higher resale value than a broken-down one, along with being more appealing to potential buyers. 

Let’s start with a basic checklist of things to look for before you start towing. While this may seem like a very dull part of your trip preparations, it’s far better to be safe in the parking lot than sorry on the road. Hopefully you won’t find any problems; but if you do, we’ll go more into depth on what to do later on! 

First, let’s look at the tires. Use a tire pressure gauge to measure your tire pressure, making sure it matches the level printed on the tire’s sidewall. Underinflated tires can lead to blowouts, so reinflate them if needed.

Visually inspect your trailer tires for any signs of damage or deformities. These include punctures, bulges, cracks in the rubber, and foreign objects lodged in the tire. While you’re doing this, check if your tire tread depth is deep enough. A common trick is to stick a penny upside down in the tread — if you can see the top of Abraham Lincoln’s head, it’s not deep enough. Proper tread depth is necessary for maintaining a grip on the road; the last thing you want is your trailer to start sliding around on smooth tires! 

Functioning trailer lights are important not only for you, but for your fellow drivers. Check that your taillights, brake lights, and turn signals are all working and bright enough to clearly see. The easiest way to do this is to have a friend stand behind your trailer and observe while you test the lights.  

You don’t need to be told how important working brakes are for the safety of you and your trailer. Inspect your trailer brake components for any signs of wear or damage. Next, perform a spin test on each of the wheels. You can do this by jacking up the trailer and spinning the wheels by hand, then applying the brake controller to see if the wheels stop spinning. If they don’t, you have a problem.

Even if everything looks okay, it’s a good idea to take a short drive in a safe area to test the brakes. Pay careful attention to how your trailer responds to braking, keeping an eye out for problems such as a lack of braking action, one wheel braking more than the others, or the brakes locking up entirely.  

You want to be absolutely certain that your trailer will remain attached to your tow vehicle while on the move, so keeping your hitch and coupler in good shape is key.

Examine your entire hitching system carefully for any signs of rust, corrosion, cracks, or any other kind of damage. Test the coupler’s latching mechanism to make sure it is not too easy nor too difficult to operate. Ensure that the coupler is not loose-fitting, as a loose coupler equals a loose connection between the trailer and the tow vehicle.

Don’t forget the safety chains! In the event of an emergency, they can be the one thing keeping your trailer attached to you. Inspect the links carefully for wear or rust. 

The suspension system refers to all the parts that connect the trailer to its wheels, including the axles, springs, and shock absorbers. Check all of these suspension components for signs of rust, wear, or damage.

Take another look at the tires: if the wear on the tires is uneven (more wear on the outside or inside edge, bald spots, etc.), that can be a sign of suspension problems. Wheels usually tilt slightly inwards at the top, but if this tilt appears too sharp, there might be an issue with the axle. Grinding or clicking sounds when rotating the wheels is another sign of trouble. Finally, try rocking the tire, making sure there isn’t excessive play. If there is, you may want to take a look at your wheel bearings.  

Grease not only protects your trailer’s components from rust, but it also lubricates and reduces friction between the different parts, lessening the wear and tear.

Make sure that any and all moving parts of your trailer are properly lubricated before you get on the road. These include the hitch, coupler, axles, wheel bearings, tongue jack, and more.  

Now it’s time to go more into depth on how to take care of your trailer, part by part. You should be able to do much of this maintenance on your own, but don’t be afraid to seek professional help from a trailer mechanic if you’re unsure! 

Tires are a part of the trailer that you are inevitably going to have to replace — tires only have a lifespan of roughly five years (give or take a few years, depending on the manufacturer). The goal of tire maintenance is to avoid having to replace them sooner.

First, make sure that you pick the right tires. You can’t just pop the tire off a car and stick it on your trailer. Trailer tires are stronger and sturdier than vehicle tires due to the greater weight they must support. You need to pick trailer tires that are the correct size and load rating (i.e., the maximum weight a tire can safely handle) for your trailer, which you can usually determine by consulting your owner’s manual. And of course, all of your tires should be identical in order to keep your ride even.

Speaking of evenness, you should keep an eye on your tire tread for any signs of uneven wear patterns. If some portions of your tire wear down more quickly than others, that could signal a problem.

For example, if the edges of your tire are more worn down than the center, then that could mean the tire is underinflated and needs to be filled up. If the center is more worn, overinflation is likely the culprit, and the tire’s air pressure should be reduced. Uneven wear can also be caused by malfunctioning brakes, bent axles, and improper cargo weight distribution.  

Other techniques for preventing uneven wear are tire balancing and tire rotation. Tire balancing ensures that the tire’s weight is equally distributed around its axis, preventing any imbalances that place greater pressure on any one portion of the tire. This is a delicate process that needs to be done by professionals. You should only have to have this done when you first install the tires or if you notice uneven wear.

Tire rotation is just what it sounds like — rotating your tires into different positions on the trailer. For a single axle trailer, just switch them from side to side. For double axle trailers, use the X pattern: front left tire to rear right position, rear right tire to front left position, front right tire to rear left position, and rear left tire to front right position. You can perform this process yourself, though you should only have to do it in the event of uneven wear OR when you drive 5,000 to 9,000 miles. Unless you’re doing a lot of towing, you likely won’t reach this mileage before your tires age out.

Trailer tires can also suffer wear and tear while they sit for extended periods of time. Changes in temperature, both hot and cold, cause the rubber to expand and contract, creating cracks and potentially deflating the tire. Exposure to the ultraviolet rays in sunlight degrades the rubber over time. When not in use, consider storing your tires in your garage, or at least covering them to protect them from the elements. Cleaning your tires with mild soap and water can also improve their lifespan.

However, sometimes the worst happens, and you find yourself with a worn or punctured tire. In this event, replacing the tire is your best — and safest — option.  

The electrical system of a trailer is the series of wires and connectors that allow electricity to flow from your tow vehicle to the trailer. Without one, you wouldn’t be able to use your trailer’s lights or let your fellow drivers know when you’re turning!

Like any electrical system, there’s always a chance for issues to arise. Thankfully, there are only so many things that could have gone wrong, so diagnosing the problem shouldn’t be too hard!

If your lights flicker or are not bright enough to clearly see, check your wires and connectors for any signs of corrosion, looseness, or damage — clean, secure, and repair or replace any problems you find, respectively.

If specific lights aren’t working — brake lights, reverse lights, turn signals — inspect and fix the wiring that connects to the malfunctioning light. If nothing appears wrong, check to see if the bulbs have burned out or if the switch within the vehicle itself has broken. Replace these as needed.

If the lights don’t work altogether, check the wiring and connectors. If nothing’s wrong, check your trailer’s fuse box and replace any blown fuses you find.  

Even if nothing is obviously wrong, it’s still a good idea to regularly inspect your electrical systems for potential problems. When examining your wiring, look for any pinches or signs of scorching along the wires. If you have any exposed bare wiring, make sure it doesn’t touch metal to avoid electrical shorts or fires. Safely secure the wires against the trailer’s frame with zip ties or cable clamps, and use coverings to protect them from the elements.

Connectors should be cleaned with a contact cleaner or wire brush to protect them from rust and corrosion. If the damage is more severe, replace them.

Don’t forget any batteries you have! To prevent corrosion, clean the battery’s terminals with a six-to-one water-and-baking-soda solution and cleaning brush. Try not to overwork your battery (the generally suggested limit is discharging 50% of its power at a time), and keep a closer eye on it when it’s exposed to extreme temperatures, as they can shorten its lifespan.  

The importance of functioning trailer brakes cannot be overstated. First, let’s look at the different types of trailer brake systems you may encounter, and what maintenance you will need to perform for each.  

Electric brakes are the most common braking system for modern trailers. They work by sending an electrical signal from the tow vehicle to activate the trailer’s brakes as needed.  

• Adjust your brake controller so the brakes respond quickly but not harshly. 
• Check for any loose or worn parts and replace them as needed. 
• Check the electromagnets for uneven wear and replace as needed.  

Surge brakes are not connected with the tow vehicle and are instead activated by the momentum of the trailer pushing against an actuator when you brake. Hydraulic brakes are very similar; the main difference is that they require a separate hydraulic brake system. These systems are usually used for smaller trailers, or boat trailers that you can expose to water without worrying about shorting out electricity-based brakes.  

• Check for any loose or worn parts and replace them as needed.  
• Clean and inspect the brake lines for kinks or damage. 
• Check the wheel cylinder for leaks and repair or replace as needed.  
• Keep the brake fluid level of the master cylinder at proper levels.  

Air brakes utilize compressed air stored in the tow vehicle to activate the trailer’s brakes. These are less common, only used in commercial trailers or heavy-duty RV trailers. 

• Check for any loose or worn parts and replace them as needed.  
• Inspect the system for air leaks. 
• Replace the filter once it becomes clogged with moisture or debris.  

Emergency brakes, otherwise known as breakaway brakes, are brakes that you will hopefully never have to use. These will activate in the event that your trailer disconnects from your tow vehicle while on the road, hopefully bringing it to a stop before any disasters occur.  

• Check the emergency brake’s battery for sufficient power levels. 
• Test the brakes in a safe location by activating the brakes and then attempting to tow the trailer.  

Regardless of the brake system your trailer uses, you want to be certain that your brake pads are in good shape. Brake pads are the part of the brake that presses against the rotor, bringing the wheel’s spinning to a stop. It’s a vital job, but it’s also a harsh one: friction wears the pads down over time, so you will need to replace them.

Signs that your current brake pads need to be retired include squeaking or grinding noises from the brakes and unusual vibrations while braking.

A quick overview of the brake pad replacement process is as follows:

• Park your trailer in a safe, sturdy place and jack up your trailer. 
• Remove the wheel so you can see the brakes.  
• Locate the brake caliper, which holds the brake pads in place. Compress the caliper’s piston to make room for the new pads. 
• Remove the old brake pads and clean the caliper and surrounding area. 
• Install the new brake pads and return the caliper into place. 
• Reinstall the tire and lower your trailer. Repeat for other wheels. 

Keeping your trailer and tow vehicle securely connected while on the move should be one of your top priorities. As such, a well-maintained coupler and hitch is vital.

Thankfully, coupler and hitch maintenance can largely be summed up in three words: inspect, clean, lubricate! 

Examine your hitch system carefully for any signs of rust, corrosion, or damage. Tighten any loose nuts, bolts, and other such fasteners you find. Test your coupler’s latch mechanism, ensuring that it opens and closes properly without jamming. Pay special attention to the safety chains — they’re your hitching system’s safety net!

If you find that any part of your hitching system is permanently damaged — a rust-infested hitch, a worn link on the safety chain, a misshapen coupler ball socket that can no longer properly accept a trailer ball — replace it. It’s your safest option! 

Thoroughly clean your hitch system with water and a mild detergent, removing any dirt and grime you can find. Check for any larger bits of debris, especially within the coupler, as these can prevent you from properly coupling your trailer.  

Apply a generous amount of lubricant to all the moving parts of your hitch and coupler. These include your hitch ball, coupler ball socket, and latching mechanisms — anywhere where metal touches metal. Lubrication prevents excessive friction against those parts, therefore preventing unnecessary and unwanted wear-and-tear.

You can also take this opportunity to apply rust-resistant paint to any exposed metal so it can better…well, resist rust!

Whenever you’re not towing your trailer, such as over the winter, consider removing and storing your hitch in a garage to safeguard it from the elements. If nothing else, use a protective cover. 

Your suspension system quite literally holds your trailer together! The axles, springs, and shock absorbers perform several important tasks:

• They connect the trailer’s body to its wheels.  
• They help evenly distribute weight across the wheels.  
• They absorb any shocks the road has to dish out, from tiny bumps to large potholes.

Given how important your suspension is, you should keep a careful eye out for any signs of trouble. These include strange creaks and other sounds, an uncomfortable ride, difficulty in steering, and too much bouncing, vibrating, and swaying on the road.

If you experience any of these problems (or if you want to play it safe), inspect your suspension system and thoroughly lubricate any moving parts. You will likely need to spray everything down first; being under the trailer, the suspension components will be exposed to a lot of dirt, salt, gravel, and general grime from the road.

Check your axle welds for signs of rust or damage. While you’re there, check that your trailer alignment is correct by measuring the distance between each end of the axle and the coupler. If these lengths are not the same, this means your axle is crooked and is likely making your ride difficult. While you can learn how to fix it yourself, professionals have the tools for more precise realignment.

Clean your springs regularly to avoid corrosion. If you notice any cracks or damage, replace the springs as soon as possible.

Inspect your shock absorbers for any leaks or signs of damage. If you need to replace them, do so in pairs so you can maintain an even performance.

If you uncover any major problems, such as a broken axle or complex alignment issue, you should seek out professional help.  

Wheel bearings are the definition of “small but mighty.” Located within a trailer’s wheel hub assemblies, wheel bearings support and help evenly distribute the trailer’s weight. Well-maintained bearings assist in keeping the wheels properly aligned.

Most importantly, they reduce the friction between the wheel and the axle, allowing the wheel to spin smoothly. If your bearings aren’t properly maintained, this can create excessive wear on the wheels and axles. In worst case scenarios, your wheels could lock up while on the move.

To keep your wheel bearings in good shape, you need to repack them or reapply grease. While you should do this on a regular schedule, signs that you need to repack them immediately include excessive heat from the tire, strange grinding sounds, and uneven tire wear. You should also examine the bearings if you have been towing your trailer a lot or if you have left it sitting still for a long time.  

Let’s walk through exactly how to repack your wheel bearings:  

• Chock the wheels you are not currently working on to hold the trailer in place, then jack up the trailer. Make sure the trailer is properly supported before you begin work.  
• Remove the lug nuts so you can then remove the wheel and tire, setting them aside.  
• Remove the dust cap with a screwdriver. Wipe away any grease so you can see the nut. Depending on the type of nut, straighten and remove the cotter pin or bend the tabs to remove the nut.  
• Carefully remove the outer bearing and set it aside. Remove the grease seal to gain access to the inner bearing. Carefully remove the inner bearing and set it aside.  
  
  • Note: The grease seal will likely be damaged in the process, so be sure to have a replacement on standby.  
• Clean and air dry the bearings. If they show any signs of wear or damage, replace them. Take this opportunity to clean and inspect the races — the surfaces the bearings rest against — and the rest of the surrounding area too.  
• Apply grease to the bearings by placing a blob of grease on your palm, sliding the edge of the bearings into the blob, pressing in the new grease, and rotating the bearings until they are full of grease. Also apply grease to the races and inner hub, being careful not to get any grease on the brakes.  
  
  • Note: Once greased, set the bearings down on a clean surface to avoid getting debris stuck on them.  
• Replace everything carefully. When replacing the nut between the dust cap and the outer bearing, be sure to adjust it to the manufacturer’s recommended bearing play — in simpler terms, you want the nut to be tight enough that the wheel won’t fall off, but loose enough that the wheel can still spin!  
• Replace the wheel and tighten the lug nuts by hand. Lower the trailer until the wheel just touches the ground so you can finish tightening the lug nuts without the wheel spinning.  
• Repeat process for each wheel.  

The tongue jack is easy to overlook, but nearly impossible to function without. This tool safely lifts your trailer’s coupler off of the hitch ball — in other words, it lets you detach your trailer from your tow vehicle! It also helps with properly leveling the trailer.

Maintenance for your tongue jack is fairly straightforward. Remove any dirt or debris that may obstruct the jack’s movements. Check that the jack’s mounting bolts are good and tight so it stays in place; the jack should be perpendicular to the ground and centered on the trailer tongue.

Lastly, lubricate any of the jack’s moving parts to avoid any stiffness or jamming. You should pay particular attention to the inner screw, as this allows the jack’s up-and-down movements. The process is as follows:  

• Remove the handle, outer casing, washer, and ball bearing.  
• Reattach the handle so you can use it to remove the screw from the inner casing. 
• Clean any rust or grime off the screw, then apply lubricant.  
• Replace the screw inside the inner casing and remove the handle again. 
• Replace the bearing, washer, and outer casing after applying grease to the bearings. Reattach the handle.  

Trailer maintenance is an ongoing process — as long as you own your trailer, you will need to take care of it. As for exactly how often you need to perform maintenance, the simplest answer is: it depends. It depends on the part of the trailer, the type of trailer, and how often you use it. You will likely need to do your own research to create a good maintenance schedule or trailer maintenance checklist, but let’s look at some suggestions. 

This is a basic check-up you should give your trailer before each use, especially if it was previously in storage:  

• Inspect your tires, checking for unusual wear patterns and that they haven’t aged out. Check that the tire pressure is high enough and inflate if needed. If you use your trailer regularly, repeat this check every 3 months or 3,000 miles.  
• Test your lights. 
• Test your brakes, paying attention to any unusual braking action.  
• Inspect your hitch, coupler, and safety chains for any signs of rust or wear. Apply lubricant to the moving parts. 

Note: If you use your trailer daily, you probably won’t have to do all of this every time you tow but be sure to still do it regularly! 

Inspect the entirety of your wiring system, looking for any loose connections, signs of damage, or other potential problems. 

Inspect your suspension system, looking for any signs of wear or damage.  

• Visually inspect your brakes either each year or every 12,000 miles. Look for signs of wear or damage, especially your brake pads.  
• Check your trailer alignment.  
• Inspect your wheel hub interiors and repack your wheel bearings.  
• Inspect and lubricate your tongue jack.  
• Inspect your trailer’s frame, looking for any cracks or signs of damage.  

Your exact maintenance schedule will depend on your trailer and how you use it; you may have to do some of these tasks more or less regularly than others. When in doubt, pay careful attention to your trailer and consult the manufacturer or professionals if you have any questions.

Lastly, let’s consider how to maintain your trailer throughout all of the seasons. Different times of the year come with unique challenges for trailer owners. We’ll go through how to tackle those challenges here.  

Winter is perhaps the biggest threat to your trailer’s well-being — frigid temperatures and damp snow can lead to damage if not properly prepared for.  

Your trailer’s water system in particular needs protection; if water remains in the pipes and holding tanks over the winter, they could freeze and burst, leaving you with costly trailer repairs. To winter-proof your water systems, do the following:

• Drain all of the water from your tanks. Open faucets to remove any residual waters in the lines.  
• Using your water pump, add antifreeze to your water systems until antifreeze comes out of all faucets, toilets, and showers.  
• Turn off the pump and switch on one faucet to release pressure from the system. 

Protecting your trailer from the elements is also important. Check your trailer’s exterior for any cracks in the frame or caulking where the cold could slip through. Store your trailer somewhere safe and dry, preferably inside a garage or storage facility. If you have to leave your trailer outside, use a protective cover that will shield your trailer from snow and rain while also allowing moisture to escape.

Inflate your tires to the recommended tire pressure, as icy temperatures can cause tires to deflate. Consider purchasing covers to further protect your wheels.

Batteries also drain more quickly in the cold. It’s best to disconnect and store your trailer’s battery somewhere warm and dry. Do the same with your propane tanks!

Finally, don’t forget to prepare your trailer’s interior. Remove any food or bedding from the trailer. To prevent the build-up of moisture (which can cause mold), use dehumidifiers and open cabinets and closets to maximize the circulation of air. Visit your trailer regularly to check for moisture build-up or other issues.  

When the snow finally melts, it’s time to get your trailer out of storage and back on the road!  Firstly, you’ll need to flush out your water systems if you previously winterized them. Turn on the water pump and open all faucets and showerheads, letting the water run through the systems until it’s clear. Flush the toilet a few times while you do this. Don’t forget to empty your antifreeze-filled gray and black water tanks afterwards!

It’s a good idea to sanitize your water system too, just to get any bacteria or mold out before you start using the water. You can do this by running a bleach-water mixture through your systems (1/4 cup of bleach for every 15 gallons your fresh water tank holds).

Reinstall your propane tanks and battery (fully charged!) from storage.

Finally, check everything. Inspect and reinflate your tires. Check your hitch, coupler, suspension, and any metal parts for rust or corrosion. Test your lights, brakes, and any electrical appliances. Inspect your frame and roof for cracks or damage, especially if you store your trailer outside. It’s a good time to do any yearly maintenance tasks, such as repacking wheel bearings, servicing brakes, and lubricating components.

Basically, make sure that your trailer is in tip-top shape as things warm up! 

As the hottest days of the year arrive, keeping your trailer cool is an ongoing process. Let’s go through some tips to keep your home-away-from-home from turning into an oven-on-wheels!

Keep your ventilation and air conditioning systems in good shape. Install a roof vent fan and plug in some portable fans to help keep air moving. Clean your AC filters and condenser coils for maximum airflow and heat exchange, respectively. A functioning AC unit should be able to keep your trailer’s interior 16 to 22 degrees cooler than outside.

Park in the shade to avoid direct sunlight, and try to position your trailer so the breeze can provide some natural air conditioning.

Insulate your trailer to keep the cold in and the heat out. Check any sealant along the walls or around the windows for cracks. Cover the windows and any skylights to keep out sunlight. Close the windows when there is no breeze or when you’re not using the roof vent.

Avoid producing excess heat in the trailer by cooking outside, taking shorter hot showers, and minimizing the use of electronics.

Finally, keep an eye on your tires — heat can cause your air pressure to increase.  

When things start to cool down again, there are a few things you can do to prepare your trailer.

Clean your trailer to get rid of any dirt and grime your trailer picked up over the year. This can help prevent rust or corrosion later on. If you’re parked under a tree, clear the roof of leaves.

Make sure your wheels and brakes are in good shape; fall weather can bring wet or even icy roads. Check your lights as well; with dusk coming sooner, you want to be sure your fellow drivers can clearly see your signals.

If you didn’t do your yearly maintenance in the spring, fall is another good time to do it.

Finally, if you’re about done with your trailer for the year, you can start your winter preparation and get your trailer ready for storage.  

Regular trailer maintenance is vital for your safety, your trailer’s safety, and your bank balance in the future. Maintenance prevents breakdowns and accidents. It also lets you spot and fix small issues before they become big problems — and costly trailer repair bills.

We know it can seem boring or time-consuming, but trust us — staying on top of your trailer maintenance is the best way to keep your trailer by your side (or more accurately, behind you) for years to come.