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How to Replace Trailer Brakes

A properly functioning trailer brake system shouldn’t be a last-minute consideration. Each owner of a trailer should become acquainted with the process of testing and installing new brake systems, both for the safety of your vehicle and for the safety of other drivers in the road.

Follow these steps to understand the basics of how to replace and remove the brakes on your trailer, and also warning signs that it’s time to purchase those brakes replaced at all.

When is the best time to replace your trailer Brakes?

There isn’t a single, specific moment at which you should put in new brakes on your trailer.

In addition, brake makers alike recommend keeping track of specific variables to provide a better understanding of the overall state that your brakes are in. These variables, like the weight of your trailer, towing frequency distances, distances traveled, towing terrain, and even your the driving style of your vehicle will affect the schedule of replacement for your trailer’s brakes.

There are couple of things to be aware of in order to maintain the quality and reliability of your trailer’s brakesand also the recommendations directly from the manual for your brake as well as ensuring your tow’s safety.

1. At 200 miles for manually adjusted Brakes

It’s recommended that brand new, fresh-out-the-dealership trailers see their brakes inspected and adjusted near the 200-mile mark.

About 200 miles are the time when drums and brake shoes are two of the main elements of the brake’s internal assembly, are “seated.” When properly seated, drums and shoes interact with the electromagnet of your brake system and the core brake controller. Together, they create the friction that stops your trailer each when you apply pressure to the brake while in the driver’s seat.

If shoes are not properly seated and drums, the process of braking is slow, inefficient or, in the worst case even risky.

After a 200-mile brake check the brakes on your trailer can be checked about once per year, at the time of annual licensing inspections, or whenever the frequency of towing your trailer requires.

2. At 12,000 Miles

Alongside annual check-ups of the brake systems, the wheel bearings need to be lubricated approximately once every 12,000 miles. For heavy-duty, regularly towed travel trailers as well as fifth-wheel RVs with a lot of miles of travel the schedules may be more frequently.

Be aware that grease and “packing” bearings isn’t the same thing as replacing the bearings. But, they are similar in the sense that accessing the outer and inner bearings requires similar steps for all-out installation of new brakes.

3. If Your Manual Recommends

Make sure you read the brake guidelines in the owner’s manual for your trailer or the one produced by your axle manufacturer. The manual should also provide the general, step-by-step directions on how to replace and install the brakes on your specific model make adjustments to shoe seating and pack the bearings correctly.

4. If Brake Performance is Generally Poor

Use common sense when you’re looking at maintenance and replacement of your trailer’s brakes. If you experience a squeaky wheel bearings, unusual brake lags, or variations in the braking pressure then it’s time to check the parts. If the adjustment of your brake shoes isn’t enough, you might need an overhaul of the system.

What do you need to replace your trailer Brakes?

The replacement of the brakes on a trailer requires a few tools to complete the installation effectively and safely. Make sure you have access to these prior to removing any of the components of the trailer wheel.

1. Proper Tools

These mechanical tools are the basic ones that be part of the toolkit when replacing the brakes on trailers:

Iron tire: to securely remove the trailer wheels.
Grease-filled pliers Ideal to grip a brake trailer’s variously sized components.
Flathead screwdriver: To perform various plying and screwing tasks.
Mallet: The quickest and most efficient method to get rid of the dust and grease.
Wire cutters are essential to remove and cut the old magnet wires in your brake and then crimp the new ones.
Torque wrench: To secure the wheel of the trailer and other brake components into place by following the manual limit.
Hammer: Ensure that the various small seals as well as washers that you’ll be installing are flush with edges.

2. General Equipment

Alongside the above tools, be sure you have these things in your arsenal:

Hydraulic car jacks: To raise the vehicle, then to support the trailer as it’s parked off-ground.
Work gloves: These gloves are particularly important when you’re packing grease into your replacement bearings. This process is that is explained in greater detail below.
The most suitable grease lubricant is one that is approved by the manufacturer of the axle, to pack the inner and outer brake bearings.

How to Replace the Trailer Brakes

Are you interested in changing your trailer’s brakes? Expert mechanics will follow these step-bystep instructions to ensure an easy, safe and hopefully pain-free electronic the installation of your trailer’s brakes.

1. Conduct a Brake Controller Check

Before you get the hands filthy, you must first examine the mechanical core of the trailer’s entire braking system, which is the controller for brakes.

Brake controllers communicate with the drum’s magnet. The majority of drivers place their controllers close to or under their dashboards, which makes it easy to reach and inspect when brake issues occur.

For the first brake controller check, go through the following information:

Wire conditions: The wires of the controller must appear smooth and solid with no visible fraying, tears, bumps or marks.
Schematic included: Make sure that your brake controller has its schematic, that is, the general wiring diagram that outlines how to wire your trailer to meet its specifications correctly.
Correct power readings as well as outputs must be sending the correct outputs to the brakes on your trailer, which you can test with an voltmeter or other similar devices.

2. Extend the Inner Brake Drum

Deconstruction of the brake drum begins by taking off the dust cap or grease cap, and then taking off a few components surrounding the spindle, or axle.

Clean the cap of grease or dust Utilize large grooved pliers or a screwdriver, orin the case of caps that are old and worn , use a mallet to remove the cap. If you are using a mallet apply forceful but controlled downward-facing strikes while turning the drum, allowing it to move slowly.
Remove the retainer for the nut: After that utilize a flat-headed screwdriver to remove the retainer for the nut and the cotter pin that secures it If there is one.
Remove the spindle nut Utilize your hands to take off the spindle nut that holds it off of the axle centrally.
Take off the outer bearing. After this, the outer wheel bearing should slide off fairly easily. It is generally advised to dispose of the outer bearings since they tend to become old and rusty.

3. Check the brake drum assembly

Once you have your brake drum’s interior component exposed, you are able to examine its internal assembly parts, including the magnet. Examine the entire brake drum assembly for:

Cracks, marks or loose springs on the surface of the drum assemblies
Drum thickness that is appropriate that is not worn away from the suggested sizes

The mechanics will then shift on the unit’s principal magnet. It is what receives the outputs from the controller that trigger the brakes on the trailer. They’ll look to determine if the magnet:

It wiggles a little when it’s pushed. This is a good thing because you don’t want rigid and congealed magnetics.
Contains four surface dots. Magnets for trailer brakes must have four dots on their face-side surface. As the magnet wears down the dots will disappear.

It is also a good opportunity to examine the star wheel. Star wheels are an adjustment spring that is located at the lower end of your magnet. Similar to the magnet itself, it will also move when you press it, but it should not feel loose.

4. Take off from the Brake Drum’s Inner Seal and Wheel Bearings.

The first step is to use wire cutters to cut your magnet’s wires right behind your drum’s backing plate. This is a difficult process, and is usually that is best left to experts.

Important note: You should perform this procedure only when installing the entire brake kit. If you don’t, you’ll disconnect your magnet-controller connection.

Start by removing the nuts and washers that hold the brake assembly to the central axle. It is also possible to remove the seal for the wheel bearing, that is often marked by manufacturers with the arrows. After the seal is removed then the remainder of the drum assembly will slide right off, leaving an unfinished axle.

5. Clean the Drum and Spindle of the Axle

Make use of the appropriate solvents to clean and spray your axle, getting rid of any grime, dirt or lubricant residue that has accumulated. The same process is applied to the brake drum inside that you just cleaned.

It’s also a good opportunity to clean and the filling zerk, emptying any grease that remains and then refilling it with a new lubricant. Examine the bearing races you have exposed in the steps 2 and 4. If they are damaged or damaged, replace them immediately. Then, apply a thin layer of fresh lubricant on your spindle.

6. Change your Inner Brake Assembly

The new drum assembly is likely to come in an assembly kit that includes all the parts and components you’ll require to build your new drum. The kits typically include but aren’t restricted to any of the following:

Shoes for right and left-sides
Fresh bolts, typically around 3/8-inch
Magnet unit
Inner bearings, often pre-grease packaged, other times not.

After removing the packaging After that, carefully position the new brake assembly inside the newly lubricated spindle. Be sure to place the right and left shoes on their respective sideways. It is also possible to coil-crimp the two wires of your assembly magnet back to where you cut them in the previous ones, right behind the plate for drums. The magnets for trailer brakes aren’t magnetically polarized, which means that both sides can be swapped in this case.

Be aware of the following scenarios that frequently occur when replacing an inner drum assembly of the brakes:

The drum will not fit between the right and left shoe The shoes should be expanded by using the tension adjuster or the star wheel, which is located on the bottom of the magnet for the brake assembly. The drum will eventually slide between the tabs.
The overall tension of the shoe isn’t correct The right amount of tension should be a small gap between the drum and the right and left shoes. There’s too much or not enough space between these components will mean you’ll have difficulty applying the right pressure to the brakes on your trailer. Although drums and shoes adjust themselves to ensure proper pressure as time passes, they should begin in a semi-appropriate ratio to ensure that you’re operating an able-to-stop vehicle.

7. Make sure to add new wheel Bearings as well as Races if You Need to

Lubricate your inner bearings prior to placing them back into the hub of the brake drum that is outside that should be lubricated. But, be aware that greaseing bearings is an unpleasant job. The ridged parts must be “packed” with grease or using a professional bearing packing tool , or by placing the blob of grease in the palm of your hand and packing it in the traditional way.

Be careful when it comes to grease packing. Each bearing should be smooth, perhaps bubbling, and lubricant capable of sliding easily back into the hub of the drum and then onto the axle. Make sure you’re using the highest temperature wheel bearing grease, too.

8. Install the new Outer Brake Bearing Components

Now, you’re in a position to connect the brake bearings on the outside and assembly parts back to the lubricated and cleaned axle. It will be connected to the inner components of your brake assembly and the newly wired magnet.

After putting the drum hub in place after putting it in place, you can start reinstalling the other drums and bearing components that you removed in the previous step, but with the reversed order. This means that you must first reinstall the hub, with its grease bearings packed and then the larger drum, and finally the wheel bearing on the outside and bearing washers, the spindle nut that holds it as well as the cotter pin the last but not last but not least — the cap for grease.

If the grease cap on your machine is worn or damaged, and is no longer able to sit squarely on top of the hub, you need to find an alternative. Grease caps are typically inexpensive however it is essential that they seal securely.

9. Return the Tire

With your brand new trailer brakes installed, you can then reinstall the tires on your trailer. Utilize a torque wrench or similar tool to tighten the lug nuts back to the specifications from the factory.

10. Test Exercise

The last step is to take your brake controller and conduct a final actuation test. This test will determine whether the electrical side of your trailer’s brake system is properly configured and that includes the crimping system wires in the step 6.

The maximum voltage outputs generated during activation will differ based on the type of trailer you have as well as the brake system. If the voltmeter or other similar testing device isn’t able to register an output of maximum voltage within less than 5 seconds or if the readings don’t correspond to the manufacturer’s schematics, it could be a problem with the brakes on your trailer. These kinds of wiring issues are not common when all procedures and specifications are handled by a trained professional.

When should you have your trailer brakes replaced by a professional

A professional mechanic who can examine or install your electronic trailer brakes could be a great relief. For many , the complexity and difficulty of replacing the proper trailer brakes is a daunting job to tackle on their own.

Always be on the side of caution when fixing your trailer, and that includes tackling the most “minor” brake issues. If any of these scenarios apply to you think about scheduling a trailer brake repair or inspection.

1. You’re not sure about the drum’s conditions

Drums for brakes can be reused. However, as one of the most important elements of the entire system of braking it is possible that you will be seeking a second opinion about the exact nature of its condition.

Local auto shops are able to examine your drums for rust that is beyond the surface. There are some that have specially-designed machines that can run drums through an energizing process known as turning which is less expensive than purchasing new drum kits all.

2. You’d like to hear a second opinion on the Tension of Your Shoe

A properly-spaced shoe is crucial for creating and maintaining high levels of friction to brakes. It may also require some finesse to establish the initial equilibrium between the gap between the drums and shoes as well as the wiggle room they allow themselves to adjust as time passes.

Professional mechanics can establish the Goldilocks-level tension in your brake system. This can ease any worries that your brakes aren’t properly seated or don’t self-adjust at optimal rates.

3. You just want the expert’s Hand

There are more than a dozen items of equipment that go in the installation of a brand new trailer brake system. Furthermore, the process of installing trailer brakes typically involves testing for electrical actuation and precise wire cutting , in addition to the physical mechanicsof the process, which adds an additional level of difficulty.

A professional installing your trailer’s brakes will ensure that the job is done swiftly and correctly. This is a powerful guarantee and puts the mind at rest as you carry thousands of pounds on the road.