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Home » What To Know When Replacing Your Trailer Brakes

What To Know When Replacing Your Trailer Brakes

The proper functioning of the trailer’s brakes should never be an afterthought. Everyone who owns a trailer must become acquainted with the process of making sure they are installing and testing new braking systems, both to ensure the safety of your vehicle and the safety of others on the road.

Follow the steps below to learn the basics on how to replace and remove your trailer’s brakes. Also, learn about warning signs that indicate it’s time for you to purchase those brakes replaced in the first place.

When is the best time to replace your trailer Brakes?

There isn’t a single, specific moment at which you should install new brakes to your trailer.

In addition, brake manufacturers alike suggest keeping track of certain factors in order to assess the general condition of the brakes. These variables, including the weight of your trailer, towing frequency distances, distances traveled, towing terrain and even the driving style of your vehicle will affect the schedule of replacement for your trailer’s brakes.

However, there are a few things to take into consideration in order to maintain the quality and durability of your trailer’s brakes- as well as recommendations straight from the 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.

Around 200 miles is the time that drums and shoes for brakes, two central components of the brake’s inner assembly, will have “seated.” Properly seated drums and shoes interact with the electromagnet in your braking system and the core brake controller. Together, these pieces ultimately cause the friction to stop your trailer each when you apply pressure to the brake on the driver’s seat.

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

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

2. At 12,000 Miles

Along with annual checks of brakes and brakes systems wheel bearings ought to be lubricated about once every 12,000 miles. For heavy-duty, regularly towed travel trailers as well as fifth-wheel RVs that see many miles in the roadway it is possible to schedule them more frequently.

It is important to note that greasing as well as “packing” bearings is not equivalent to replacing the bearings. But, they are similar in that accessing the inner and external bearings will require similar steps to complete the process of installing new brakes.

3. If Your Manual Recommends

Review the brake suggestions in your trailer owner’s manual or produced by your axle manufacturer. This manual will also outline the generalizedstep-by-step procedures on how to replace and install your particular brake component for your model, adjust shoe seating and ensure that your bearings are properly packed.

4. If Brake Performance is Generally Poor

Be a good steward when you’re looking at maintenance and replacement of your trailer’s brakes. If you are noticing noisy wheel bearings, unusual brake lags or differences in the braking pressure you should be looking at parts. If you find that adjusting your brake shoes does not work, it might need replacement of the system.

What do you need to do to replace the Trailer Brakes?

The replacement of the brakes on a trailer requires a few equipment to install the replacement securely and effectively. Be sure that you own or have access to these prior to removing any of the trailer wheel parts.

1. Proper Tools

These mechanical tools are the basic ones that comprise the toolkit changing the brakes on the trailer:

The tire iron is used to securely remove trailer wheels.
The pliers with grooves are Ideal as a grip for a truck brake’s varying size parts.
Flathead screwdriver: To perform various screwing and plying steps.
Mallet: For the most efficient method of use, it is the most efficient way to eliminate the initial dust and grease.
Wire cutters are essential to remove and cut the brake’s magnetic wires and then crimp the new ones.
Torque wrench: To tighten the wheel of the trailer and other brake components by following the manual limit.
Hammer: Ensure that any smaller seals and washers you’ll be installing are flush with edges.

2. General Equipment

In addition to the above tools, be sure to have the following items on hand:

Hydraulic carjack: to prop the vehicle up, then help support the trailer when it’s mounted off the ground.
Work gloves: These gloves are particularly important if you’re packing grease into replacement bearings. The process is which is further explained below.
An appropriate grease lubricant should be an approved product by the manufacturer of the axle, for packing the outer and inner brake bearings.

How to Replace Trailer Brakes

Are you thinking of replacing your trailer brakes? Expert mechanics will follow these step by step instructions to ensure the smooth, secure and, hopefully, headache-free electric installing of the brakes on your truck.

1. Conduct a Brake Controller Inspection

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

Brake controllers connect and communicate with the brake drum’s magnet. A majority of drivers put their controllers close to or under their dashboards, making it easy to access and examine if braking issues develop.

To run an first brake controller check, you must review the following information:

Wire conditions: Controller wires must appear smooth and solid with no visible fraying, tear, or bumps.
Schematic included: Ensure that your brake controller still has its schematic, that is, its general wiring diagram signaling how to wire your trailer in accordance with its specifications in a proper manner.
Properly calibrated power readings as well as outputs must be sending the correct outputs to the brakes on your trailer, which you can check using an voltmeter or other similar equipment.

2. Detach the Brake’s Inner Drum

The deconstruction of the brake drum starts by eliminating the dust or grease cap. Then, taking off a few components within the center spindle, or axle.

Remove the cap that is clogged with dust or grease Utilize large pliers with grooves as well as a screwdriver orfor caps that are older and worn-out, the mallet to break off the cap. If using a mallet apply forcible but controlled upward-facing hits while spinning the drum, allowing it to move slowly.
Remove the nut retainer. Next utilize a flat-head screwdriver, to break off the nut retainer , and then the cotter pin that secures it in the event that one exists.
Remove the spindle nut Utilize your hands to pull the spindle nut retaining it out of the center axle.
Remove the outer bearing: After this, the outer wheel bearing will slide off fairly easily. It is generally advised to dispose of outer bearings, as these parts tend to get older and get rusty.

3. Check the brake drum assembly

With the brake drum’s inner piece exposed you are able to examine its internal assembly, and the components that make up the magnet. Inspect the brake drum assembly for:

Cracks, scores or loose springs that are strewn across the surface of the drum assemblies
Properly sized drums Not worn down from the suggested sizes

Mechanical engineers will then turn their attention to the unit’s central magnet, which is what receives outputs from the controller to engage the trailer brakes. They’ll determine if the magnet

Wiggles around a bit when you push it. This is great — you don’t want stiff and congealed magnetics.
Contains four surface dots. Trailer brake magnets should contain four dots on the face surface. When a magnet wears down these dots vanish.

This is also an excellent place to test the star wheel. Star wheels are a tiny adjustment spring at the bottom of your magnet. Just like the magnet itself it’s supposed to wiggle when you press it, but it shouldn’t feel loose.

4. Take off all Brake Drum’s Inner Wheel Bearing and Seal Components

The first step is to use wire cutters and cut the magnet’s wires right behind the backplate of your drum. This can be a daunting task, but is typically that is best left to experts.

Important note: Make this procedure only when installing the entire brake assembly kit. In the event that you fail, you’ll permanently disconnect your magnet-controller connection.

Begin by unscrewing the nuts as well as the washers that hold the brake assembly to its central axle. It may also be necessary remove the wheel bearing seal, that many manufactures mark with an arrow. After that then the remainder of the drum assembly should slide right off, leaving you with an unfinished axle.

5. Clean the Removed Drum and Axle Spindle

Use appropriate solvents to spray and clean your axle, clearing any grime, dirt or lubricant residue that has accumulated. Make the same procedure for your interior brake drum you’ve just removed.

This is also a great time to clean and grease your unit’s filling zerk, emptying any remaining grease and filling it with a new lubricant. Inspect the bearing races you exposed in the steps 2 and 4. If they are damaged or chipped, find replacements immediately. Then, apply a thin layer of fresh lubricant onto your spindle.

6. Replace the Inner Brake Assembly

The new drum assembly is likely to come in an assortment of parts and components that you’ll require to build your new drum. These kits are typically comprised of but aren’t limited to the following:

Right- and left-side shoes
Fresh bolts are typically about 3/8-inch
Magnet unit
Inner bearings, often pre-grease packed, other times not.

Once removed from its packaging Then, gently place the new inner brake assembly on the newly lubricated spindle. Be sure to place the left and right shoes on their respective sideways. You can also coil-crimp your assembly magnet’s two wires back in the same spot you cut them in the previous ones, on the opposite side of that drum’s plate. Trailer brake magnets aren’t polarized, so the negative and positive sides can be used interchangeably at this point.

Keep in mind the following situations that often come up when replacing the inner brake drum assembly

The drum isn’t able to fit over the left and right shoe: Expand the shoes by activating the tension adjuster or star wheelthat is situated near the bottom of the brake assembly’s magnetic. The drum should eventually slide between the two tabs.
The overall tension of your shoes isn’t as good: There should be a tiny gap that is left between the drum as well as the right and left shoes. A lot or too little space is left between these parts will mean you’ll have difficulties applying enough pressure to your trailer brakes. While shoes and drums adjust themselves to ensure proper pressure as time passes, they should start off at a suitable spatial ratio to ensure that you’re driving an able-to-stop vehicle.

7. Include New Wheel Bearings as well as Races if Not Required.

Lubricate your inner bearings prior to adding them to the hub on the outside of your brake drum that should be lubricated. It is important to note that greaseing bearings can be a dirty job. These ridged pieces must be “packed” with grease or using a professional packing device or by putting the blob of grease in your palm and packing it in the old-fashioned way.

Be careful when it comes to grease packing. It is important for each bearing to be slickedclean, even flowing, with lubricant able to slide easily back into the drum hub and onto the axle. Be sure to use only premium wheel bearing grease as well.

8. Reinstall the New Brake Outer Bearing Components

You’re now prepared to join the outer brake bearings and assembly parts back to the clean and lubricated axle. This will connect it with the inner components of your brake assembly which includes the newly wired magnet.

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

If your grease cap is damaged or damaged and it isn’t able to fit squarely over an axle, look for a replacement. Grease caps are typically inexpensive but it’s important to seal them tightly.

9. Return the Tire

With all of your new trailer brakes installed, you can be able to reinstall your tires. Utilize a torque wrench or similar tool to force the nuts to their specific factory specifications.

10. Test Practice

The last step is to grab your brake controller to run a final test of actuation. This test checks if the electric side of your trailer’s brake system is properly configured, namely the crimping system wires back in Step 6.

The maximum voltage outputs you can expect to see during your action will be different based on the type of trailer and your brake kits. However, if the voltmeter or similar device fails to show an output of maximum voltage in less than five seconds or if the results don’t conform to the schematics of the manufacturer, there might be a persistent issue related to the brakes for your trailer. Problems with wiring like this are rare when all installation steps and details were carried out by a skilled professional.

When to Have Trailer Brakes replaced by a professional

Having a professional mechanic inspect or install your electronic trailer brakes could be a welcome relief. Many people find that the complexity and difficulty of repairing your trailer’s brakes is an overwhelming task to undertake on their own.

Always take a step of cautiousness when working on your trailer, and that includes tackling the most “minor” brake issues. If any of the following scenarios apply to you think about scheduling a trailer brake examination or fix.

1. Are you unsure of the conditions for drums?

Drums for brakes can be reused. But as one of the most important elements of the entire system of braking, you may find yourself wanting a second opinion on the true nature of its condition.

Local auto repair shops can check your drums to see if they have surface rust. Some even have special machines that allow drums to undergo an energizing process known as turning which is less expensive than purchasing new drum sets in the end.

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

The correct seating of shoes is vital to creating and maintaining good levels of friction that can be used for brakes. It may also require a little finesse, particularly in determining the balance between drum-shoe gaps and flexibility before they adjust themselves in time.

Professional mechanics can set that Goldilocks-level amount of tension in your brake system. This will eliminate any concerns your brakes aren’t seated properly or aren’t self-adjusting at the appropriate rates.

3. You Just Want the Expert’s Hand

There are nearly a dozen parts of equipment involved in the installation of a brand new trailer brake system. Furthermore, the process of installing trailer brakes is usually involving electrical actuation tests and precise cutting of wires in addition to the physical mechanicsof the process, which adds another daunting layer of work.

Having a professional install your trailer’s brakes will ensure that it’s done fast and correctly. The guarantee is strong that will put the mind at rest as you haul thousands of pounds down the highway.