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What Do You Need to Replace Trailer Brakes?

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A properly functioning trailer brake system must never be left to chance. Every trailer owner should grow comfortable with the process of making sure they are installing and testing new braking systems — both for the safety of the rig and the safety of others in the road.

Follow the steps to learn the basics of the best way to replace and remove your trailer’s brakes. Also, learn about warning signs that indicate it’s time for you to get those trailer brakes replaced in the first place.

When Should You Replace Trailer Brakes?

There isn’t one definitive point where you must put in new brakes on your trailer.

In addition, brake manufacturers too recommend monitoring certain variables in order to assess the general condition of the brakes. The variables you consider, for instance, the weight of your trailer, its towing frequency and distances traveled, as well as towing terrain and even driving style can all impact the timing of your replacement for brakes on your trailer.

However, there are couple of points to keep in mind in order to maintain the quality and durability of your trailer’s brakes -along with recommendations straight from your brake’s manual in order to ensure 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 drums and brake shoes two major elements of the brake’s internal assembly, will have “seated.” When properly seated, drums and shoes interact with the electromagnet in your braking system and the core brake controller. Together, these two pieces trigger the friction that stops your trailer each time you press down on the brake in the driver’s seat.

In the absence of properly-seated shoes and drums, braking will be inefficient, slow or — in the worst-case scenario — even dangerous.

After a 200-mile brake check the brakes on your trailer can be reviewed approximately once a year during annual licensing inspections or as much as the towing frequency of your trailer calls for.

2. At 12,000 Miles

Alongside annual brake system inspections, wheel bearings should be lubricated roughly per 12,000 miles. For regularly towed heavy-duty travel trailers and fifth-wheel RVs that travel a lot of miles on the roads these schedules might be more often.

Take note, however, that grease as well as “packing” bearings is not the same thing as replacing bearings. However, the two are similar processes in that accessing both the inner and outer bearings will require comparable steps for all-out installation of new brakes.

3. When Your Manual Recommends

Make sure you read the brake guidelines in your owner’s manual of your trailer or the one produced by your axle manufacturer. That manual should also explain the generalized, step-by-step instructions for how to replace and install your particular brake component for your model Adjust shoe seating, and pack the bearings correctly.

4. If Brake Performance is Generally Poor

Apply common sense when it comes to the maintenance and replacement of your trailer’s brakes. If you’re experiencing noise from wheel bearings or odd brake lags, or variations in the braking pressure, it’s time to inspect parts. If adjusting the brake shoes isn’t working, you may need a system replacement.

What Do You Need to do to replace the Trailer Brakes?

The replacement of the brakes on a trailer will require a handful of tools for installing the system effectively and safely. You must have access to the following prior to removing any of the wheels from your trailer.

1. Proper Tools

These essential mechanical tools will constitute the toolkit for replacing the brakes of the trailer

Tire iron: For safely remove trailer wheels.
Grease-filled pliers Ideal for gripping a trailer brake system’s disparately sized parts.
Flathead screwdriver: To perform different plying and screwing steps.
Mallet: The quickest and most effective method to take off the dust and grease.
Wire cutters: essential for cutting and removing your brake’s old magnet wires and crimp its new ones.
Torque wrench: To tighten the wheel of the trailer and other brake pieces into place according to the manual limitations.
Hammer: Making sure various smaller seals and washers you’ll be installing sit flush around edges.

2. General Equipment

Alongside the tools mentioned above, be sure you keep the following things in your arsenal:

Hydraulic carjack: to prop the vehicle up, then support the trailer while it’s mounted off the ground.
Work gloves: Work gloves are especially important when you’re packing grease into replacement bearings. This is that is explained in greater detail below.
A suitable grease lubricant for your needs: Ideally an approved product by the axle manufacturer, to pack the inner and outer brake bearings.

How to Replace Trailer Brakes

Are you considering replacing your trailer brakes? Professional mechanics follow these step by step instructions to ensure that the process is safe, smooth and, hopefully, head-ache-free electric the installation of your trailer’s brakes.

1. Conduct a Brake Controller Inspection

Before you can get your hands dirty, first look at the mechanical heart of the entire trailer’s brake system, which is The brake control.

Brake controllers are connected and communicate with the drum’s magnet. A majority of drivers put their controllers on or near their dashboards, making it simple to access and examine if braking issues develop.

To run an first brake controller check, read the following items:

Wire conditions: The wires of the controller should appear clean and straight, without visible fraying, tear, or bumps.
Schematic included: Make sure that your brake controller has its schematic — that is, its general wiring diagram signaling how to wire your trailer according to its specs in a proper manner.
Proper power readings as well as outputs must have the proper outputs for your trailer brakes, which you can verify using the voltmeter, or any similar devices.

2. Extend the Inner Brake Drum

Deconstruction of the brake drum begins by getting rid of the dust cover or grease cap. After that, the removal of a few pieces within the center spindle, or axle.

Clean the cap of grease or dust Utilize large grooved pliers or a screwdriver, or- when caps are older and worn-out, the mallet to break off the cap. If using a mallet, apply forcible but controlled downward-facing strikes while turning the drum to loosen it slowly.
Take off the nut retainer. Next make use of a big flathead screwdriver to push off the nut retainer , and then the securing cotter pin, if there is one.
The spindle nut is removed Use your hands to remove the spindle’s retaining nut from the central axle.
Remove the outer bearing The outer wheel bearing should slide off quite easily. It is generally advised to dispose of outer bearings as they can become older and get rusty.

3. Inspect the brake drum assembly

When you have your brake drum’s internal piece exposed you are able to now look at its inner assembly components, which includes the magnet. Check the overall brake drum assembly for:

Cracks, scores or loose springs on an assembly’s drum surface
Drum thickness that is appropriate, not worn down away from suggested sizes

The mechanics will then shift their attention to the unit’s center magnet. The magnet is what receives inputs from the controller, which are used to activate the brakes on the trailer. They’ll check to see if the magnet

It wiggles a little when pushed. This is fine — you don’t want rigid or congealed magnets.
Contains four surface dots. Trailer brake magnets should contain four dots on their face-side surface. As the magnet wears down these dots fade away.

This is also an excellent spot to inspect your star wheel. Star wheels are a tiny adjustment spring that is located at the bottom of the magnet. Similar to the magnet itself, it should also wiggle when it is pressed, but it shouldn’t be achy or sloppy feeling.

4. Remove your Brake Drum’s Inner Seal and Wheel Bearings.

The first step is to use wire cutters to cut off your magnet’s wires just behind the drum’s backplate. This is an intimidating procedure, but it is often better left to the pros.

Important note: Make this procedure only when you’re installing an entirely new kits for brakes. Otherwise, you’ll permanently end your connection to the magnet controller.

Begin unscrewing the nuts and washers that secure the brake assembly to its central axle. You may also have to loosen the wheel bearing seal, that many manufactures mark with an arrow. When the seal is unloosened it, the rest of the drum assembly should slide right off, leaving an empty axle.

5. Clean the Drum, and Spindle of the Axle

Make use of solvents that are suitable to spray and clean your axle, removing any dirt, grime or residual lubricant that’s accumulated. Make the same procedure for the interior drum of your brake that you just cleaned.

This is also an excellent time to wash and grease your unit’s Zerk filling. You can do this by taking out any residual grease and refilling it with a new lubricant. Check the bearing race you exposed in Steps 2 and 4. If any are scarred or damaged, replace them immediately. Also, put a light coating of fresh lubricant onto your spindle.

6. Change the Inner Brake Assembly

The new drum assembly likely comes in kits that contain 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, generally around 3/8-inch
Magnet unit
Inner bearings are pre-grease filled, sometimes not

Once removed from its packaging, carefully place the new inner brake assembly onto the spindle that has been lubricated. Be careful to position the left and right shoes in their appropriate faces. It is also possible to coil-crimp the two wires of your assembly magnet back in the same spot you cut them on the previous ones, on the opposite side of that drum’s plate. Trailer brake magnets aren’t in polarization, so the positive and negative sides can be used interchangeably at this point.

Take note of the following scenarios that typically come up when replacing the inner brake drum assembly

The drum will not fit between the right and left shoe: Expand the shoes by using the tension adjuster or star wheel, situated on the top of the brake assembly’s magnetic. The drum will eventually move between the tabs.
The overall tension of the shoe isn’t correct: There should be a small gap between the drum as well as the left and right shoes. A lot or too little space is left between these parts, and you’ll have difficult time applying the proper pressure to your brakes for your trailer. Even though drums and shoes do self-adjust for proper pressurization with time, they have to begin at a suitable spatial ratio to ensure you’re driving in a safe and stoppable vehicle.

7. Make sure to add new wheel Bearings as well as Races If Needed

Clean your inner bearings prior to applying them back into the hub on the outside of your brake drum and ensuring that they are lubricated. However, do note that greaseing bearings can be dirty work. These ridged pieces must be “packed” with grease either by using a professional packing device or by putting a blob in your palm and packing it the traditional method.

Do not be overly generous when packing. Each bearing should be slicked, even a little flowing, with lubricant and able to slide back into the drum hub and then onto the axle. Make sure you’re using the highest temperature wheel bearing grease as well.

8. Reinstall the new outer brake Bearing Components

At this point, you’re prepared to join the outer brake bearings and assembly components back over the lubricated and cleaned axle. It will be connected to the brake assembly’s inner components, including the magnet that you have wired.

Once you’ve positioned the drum hub, you can begin reinstalling the other drums and bearing components you removed in step 2 but with the reversed order. That means reinstalling first the hub and its grease bearings packed first, then the bigger drum, the outer wheel bearing and bearing washers, the retaining spindle nuts, the cotter pin and — last but not last but not least — the cap that holds grease.

If the grease cap on your machine is worn or damaged, and is no longer able to sit squarely on top of an axle, look for an alternative. Grease caps are typically inexpensive but it’s critical they seal securely.

9. Return the Tire

Once you have all your new trailer brakes set, you are able to then reinstall the tires on your trailer. Utilize a torque wrench or similar tool to tighten the lug nuts back to their designated factory specs.

10. Test Exercise

And lastly, take your brake controller and run a final actuation test. This test checks to see if the electric side of your trailer’s brake system has been configured correctly by crimping the system wires back into the system 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. However, if the voltmeter or other similar testing device isn’t able to register a maximum voltage output in less than five seconds, or if readings don’t correspond to the manufacturer’s schematics, it may be a lingering problem with the brakes on your trailer. These kinds of wiring issues are uncommon when all procedures and specifications were carried out by a trained professional.

When is the best time to have your Trailer Brakes Replaced Professionally

The services of a professional mechanic to inspect or install your electronic trailer brakes could be a welcome relief. For many , the technical aspect and the importance of repairing your trailer’s brakes is too big a task for them to handle on their own.

Always take a step of caution when the maintenance of your trailer, which includes dealing with some “minor” brake problems. If any of these situations are relevant to your situation take into consideration scheduling a trailer brake repair or inspection.

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

Brake drums can be used again. But as one of the most important components of the entire system of braking, you may find yourself looking for a second opinion regarding the exact nature of its condition.

Local auto shops are able to examine your drums past surface rust. Some even have special machines that allow drums to undergo an rejuvenation process, known as turning which is less expensive than buying new drum kits completely.

2. Do You Need a Second Opinion on the Tension of the Shoe

The correct seating of shoes is vital to creating and maintaining good levels of friction when stopping. It also requires some finesse to find that initial harmony between the gaps between the drum-shoes as well as the wiggle room they allow themselves to adjust with time.

Professional mechanics are able to set that Goldilocks-level amount of tension within your new brake system. This can ease any worries your brakes aren’t seated properly or aren’t self-adjusting to healthy rates.

3. You just want the expert’s A Touch

There are nearly a dozen components that go to install a brand-new trailer brake kit. What’s more, installing trailer brakes almost always involves electrical actuation tests and precise wire cutting in addition to the physical mechanicsof the process, which adds an additional level of difficulty.

The use of a professional to install your trailer’s brakes guarantees that it’s completed quickly and properly. The guarantee is strong and will set the mind at rest while you carry thousands of pounds down the road.