Carl’s Trailer Sales

Trailer brakes not working

Electric trailer brakes need power from the tow vehicle, a brake controller that is on, and a plug that is fully seated. If the trailer does not slow when you expect it to, stop the trip and sort it out before the load gets bigger.

This is a shop-level check, not a wiring lesson. Carl’s can test magnets, wiring, and the breakaway battery on a trailer in Belle Fourche. If the brakes are required for the weight you are hauling, do not keep driving on the hope that the truck brakes will cover it.

Start here

The first four checks

How electric trailer brakes get power

Most stock and horse trailers with electric brakes use an electromagnet inside each brake. The tow vehicle sends power through the trailer plug. A brake controller in the cab decides how much. Manual levers on the controller let you apply the trailer brakes without stepping on the truck pedal. That is the feel test people use in an empty lot.

If the brake controller shows no connection, or the manual lever does nothing, the fault is often the connector, the controller power, or a broken wire between the connector and the axle. Carl’s can find which one. We will not print a pin-by-pin wiring recipe here. A wrong wire can lock a brake or leave you with none. The shop test covers the brake magnets, the brake shoes, and the brake drum. Hydraulic brakes are a different system and do not use this controller.

What you can check before the shop

Turn the controller on and set the gain where you can feel the trailer tug when you use the manual lever, in a safe open area, at low speed. If you feel nothing, unplug the 7-way, look for bent pins or corrosion, and push it back in until it seats. A connector that runs the lights can still miss the brake circuit.

Look at the breakaway switch on the trailer tongue. The pin should be in the switch, and the cable should be clipped to the tow vehicle so it pulls only if the trailer separates. A pin left out on purpose, or knocked out in a yard, can apply the brakes the whole time you drive. It can flatten the breakaway battery, and the switch does nothing on the day you actually need it.

After those checks, stop. Magnets wear. Wiring rubs through at the axle. A weak breakaway battery will not show up in a glance. That is the trailer service visit.

Brakes and the weight you are hauling

A light empty trailer can feel fine with weak brakes. The same trailer loaded with cattle, horses, or a stack of panels will push the truck. Match the brake system to the GVWR on the trailer placard, not to how it felt on the last empty haul.

If you are still choosing a trailer, look at trailers for sale, including stock trailers and horse trailers. Ask which axles have electric brakes before you leave the lot.

Bring the trailer to Belle Fourche

Carl’s Trailer Sales is at 10958 US HWY 212, Belle Fourche, SD 57717. Tell us whether the controller shows a connection and whether the breakaway pin was in. We will test from there.

Schedule trailer service

Common questions

Why are my trailer brakes not working?

Start with the controller power and gain, a fully seated 7-way plug, and the breakaway pin in the switch. If those are right and you still feel nothing, the magnets, wiring, or breakaway battery need a shop test.

The lights work. Why don’t the brakes?

Running lights and electric brakes use different circuits in the connector. A connector can pass light power and still miss the brake pin. Seat it again, then have the brake circuit tested if the brake controller still shows no connection.

What does the breakaway switch do?

It applies the trailer brakes if the trailer separates from the tow vehicle. The pin should stay in the switch during normal towing. A pin left out can lock the brakes or drain the breakaway battery.

Can Carl’s test trailer brakes?

Yes. Bring the trailer to Carl’s Trailer Sales in Belle Fourche. Call (605) 892-4032 or use the trailer service page to set a time.

Aluminum or steel is a tradeoff, not a winner

The aluminum vs steel trailer question comes down to four things: weight, rust, repairs, and price. Steel trailers usually cost less up front and are easier to get welded. Aluminum trailers weigh less empty and do not rust the way bare steel does. Both can be built strong. Both need care. The right one depends on what you haul, how often you pull it, where you park it, and how long you plan to keep it.

This is a real choice on our lot. We carry aluminum gooseneck stock trailers from Wilson and Hillsboro, steel stock and flatbed trailers from Circle D, steel flatbed, dump, and utility trailers from H&W, and steel Iron Bull dump trailers. Even our truck flatbeds come in both, with aluminum and steel beds from Hillsboro.

We will not tell you one metal is always better. We will show you the actual trailers, the plates, and the prices so you can decide.

Aluminum vs steel trailers at a glance

These are general tradeoffs. Design, frame size, floor, axles, and how the trailer is used matter as much as the metal.

Aluminum vs steel trailer weight

Every pound the trailer weighs empty is a pound of its rating you cannot use for cattle, hay, or equipment. That is the main reason people pay more for aluminum. Aluminum construction is the lightweight side of an aluminum vs steel trailer. On a long trip, that lower empty weight can leave more of the tow vehicle’s payload capacity for the load. Read the GVWR and the empty weight before you treat that as a number. A lighter trailer can be easier on your truck over a long pull to the sale barn.

Do not assume the savings, though. Compare the two actual trailers you are looking at. Read the GVWR on each certification label and get the real empty weight. Then do the math in our trailer GVWR vs payload guide. A heavier steel trailer with a higher GVWR can still carry more than a lighter aluminum one with a lower rating.

Your truck still has to be rated for the loaded trailer. The hitch still has to match the trailer. If the hitch type is an open question, read bumper pull vs gooseneck trailers next.

Rust and corrosion: neither metal gets a pass

Steel rusts once water reaches bare metal. It does not have aluminum’s corrosion resistance. Gravel chips, scraped gates, and worn floors are where it starts. Catch it early. Sand the spot, let it dry, and touch it up with rust-proof paint.

Aluminum does not rust, but it is not maintenance free. Featherlite, which builds aluminum trailers, warns that horse urine and manure can corrode aluminum floors. It also tells owners to wash the whole trailer right after exposure to road salt and deicer. If you haul livestock, pull the mats and clean under them. If you pull through winter, rinse the trailer when you get home.

Either way, a trailer parked dirty and wet wears out faster. Washing is the cheapest repair you will ever make.

Strength and repairs

A well-built aluminum trailer and a well-built steel trailer can both carry their rated load. Strength comes from the design, not just the metal. Read the GVWR and axle ratings instead of judging by the material.

Repairs are a real difference. Steel is the metal most welding shops work with every day. Aluminum takes different equipment and experience, so fewer shops do it well. Ask where the trailer will be fixed before you buy it.

That question has an easy answer here. Wareing Carl’s Trailer Sales is an authorized Wilson Gooseneck and Semi Trailer repair center, and our trailer service and repair shop works on the trailers we sell.

Price: what the difference looked like on our lot

Aluminum usually costs more. Here is a real example. When we checked our listings in October 2026, new 7′ x 24′ aluminum Wilson gooseneck stock trailers were listed from $30,750 to $34,350. A new 7’6″ x 24′ aluminum Hillsboro was listed at $32,250. A new 6’8″ x 24′ Circle D gooseneck stock trailer, from a steel trailer builder, was listed at $19,100.

Those trailers differ in width, compartments, and features, so treat that as a direction, not a quote. Prices and inventory change. Check the current trailer inventory for today’s numbers, and weigh the higher price against how long you plan to keep the trailer.

Which metal fits which trailer?

Stock and horse trailers

This is where the choice comes up most. Aluminum suits owners who haul often and far, and who will keep up with washing. Steel suits owners who want the lower price and haul shorter distances. Compare both on our stock trailers and horse trailers pages.

Flatbed, dump, and utility trailers

Most of the flatbed, dump, and utility trailers on our lot are steel, from builders like H&W, Circle D, and Iron Bull. If you are weighing an aluminum vs steel utility trailer for ranch work, steel is what most of our utility trailers are made of. Gravel, skid steers, and equipment are hard on a deck, and steel is simple to repair after a rough season. See the flatbed trailers and dump trailers pages.

Enclosed trailers

Our new E-Z Hauler enclosed trailers are listed as all-aluminum builds. If you pull an enclosed trailer behind a half-ton or an SUV, lower empty weight helps. See enclosed trailers.

Used trailers

On a used steel trailer, look for rust at welds, crossmembers, and the floor. On a used aluminum trailer, look for cracks near welds, corrosion under mats, and loose rivets. Browse used trailers and ask us to walk it with you.

Questions to answer before you pick

• What do you haul, and how heavy is a full load?
• How many miles a year will the trailer travel?
• Will it see road salt, or sit outside year round?
• Will you wash it after every livestock haul?
• What is your truck’s tow rating and payload?
• Where will you get it repaired if a gate or crossmember gets bent?
• How long do you plan to keep it?

The metal is not the whole trailer. Aluminum construction is the lightweight path, and that can change payload capacity once you read the GVWR. Corrosion resistance is real on aluminum, and corrosion still shows up if urine or road salt sits. Tires wear on their own. Our trailer tire guide covers how long trailer tires last. The hitch still has to match, bumper-pull or gooseneck. On the highway, a lighter trailer can mean less strain on the tow vehicle. Durability still comes from the build, the wash maintenance, and where you get it repaired. The right trailer is the one whose material, price, and repair plan match the work. The safety check is the truck’s tow rating and the trailer’s GVWR.

Aluminum vs steel trailer FAQ

Are aluminum trailers better than steel trailers?

Not always. Aluminum weighs less empty and does not rust, but it usually costs more and needs a shop that can weld aluminum. Steel usually costs less and is easier to repair, but it needs paint touch-ups to keep rust away. What you haul and how you use the trailer decide the better choice.

Do aluminum trailers rust?

Aluminum does not rust like steel, but it can corrode. Featherlite warns that urine and manure can corrode aluminum floors and recommends washing the trailer right after it is exposed to road salt or deicer.

What are the downsides of an aluminum trailer?

The main ones are price and repairs. Aluminum trailers usually cost more up front, and fewer shops can weld aluminum well. Aluminum can corrode if urine, manure, or road salt sits on it, so it needs regular washing.

Do aluminum trailers last longer than steel trailers?

They can, because aluminum will not rust out the way neglected steel does. Care matters more than the metal, though. A steel trailer that is washed and touched up can last a long time, and an aluminum trailer that sits dirty can still corrode.

Is an aluminum trailer worth the extra cost?

It can be if you haul often, pull long distances, or plan to keep the trailer a long time. If you haul a few times a year close to home, a steel trailer may make more sense. In October 2026, new aluminum 24-foot gooseneck stock trailers on our lot were listed well above a new 24-foot Circle D, so compare the actual trailers.

Can I haul more with an aluminum trailer?

Only if the numbers say so. Payload is the trailer’s GVWR minus its actual empty weight. A lighter trailer leaves more room for cargo only when the GVWR is the same or higher. Check the label on each trailer and weigh it empty.

Which is easier to repair, steel or aluminum?

Steel. Most welding shops work with steel. Aluminum repairs need different equipment and experience. Wareing Carl’s Trailer Sales is an authorized Wilson Gooseneck and Semi Trailer repair center in Belle Fourche.

Does Wareing Carl’s Trailer Sales sell both steel and aluminum trailers?

Yes. We carry aluminum stock trailers from Wilson and Hillsboro, steel trailers from Circle D, H&W, and Iron Bull, all-aluminum E-Z Hauler enclosed trailers, and aluminum or steel truck flatbeds.

Compare aluminum and steel on one lot

Wareing Carl’s Trailer Sales, 10958 US HWY 212, Belle Fourche, SD 57717. Customers come from Spearfish, Sturgis, Rapid City, and nearby ranches.

Carl’s Trailer Sales

Trailer tires often age out before they wear out. A stock trailer can sit for months, then take a loaded trip to the sale barn. The tread can still look deep when the sidewall has been baking in the sun. That is why “how many miles” is the wrong first question.

Storage changes the life of trailer tires, and miles are only part of the story. Trailer tires stored in the sun can crack in the sidewall. People call those cracks dry rot. A tire that sits can flat-spot. Check tire pressure when the rubber is cold, and match the load range printed on the sidewall to the placard on the trailer. The spare on a stored trailer ages on the same clock.

There is no federal rule that says every trailer tire must come off at one birthday. NHTSA tells you to stop using a tire that is worn, cut, cracked, bulged, or damaged by low pressure or too much weight. NHTSA says some vehicle and tire manufacturers recommend replacing tires that are 6 to 10 years old, even when the tread remains. Your tire maker and the placard on the trailer are the instructions that apply to your setup.

Start here

The short version

Read the date code first

The age starts with the DOT Tire Identification Number on the sidewall. It begins with the letters DOT. The last four digits are the week and the year the tire was built. NHTSA’s example is 0308, which means the third week of 2008. A code ending in 0921 means the ninth week of 2021. Goodyear uses the same reading in its RV tire bulletin.

Look at both sidewalls. NHTSA says the full number may be on only one side. Write the four digits down before you decide the tire is “about five years old.” A tire can sit in a warehouse before it is mounted, so the build date is not the same thing as the day it was first put in service.

What the tire makers actually say

Goodyear’s RV bulletin, published through NHTSA, is careful about this. It says calendar age alone cannot predict when an RV tire should be replaced, and that no single scientific timetable covers every tire. The 6-year in-service recommendation is Goodyear’s guidance for RV tires, including the spare. It is not a law that covers every utility trailer in the county. If your tires are a different brand, follow that brand.

Walk every trailer tire

Do not stop at the tire closest to the shop door. Trailer tires on the sunny side and trailer tires on the shady side can tell two different stories. Check each tire, then the spare.

On every tire, read the date code, look at the tread, and feel the sidewall. Trailer tires with deep tread can still show dry rot. Trailer tires with even wear can still be old. Write down what you see so a clean tire does not talk you out of looking at the next one.

Wheels matter with the tires. A bent wheel, a loose lug, or a tire that sits crooked on the axle is a reason to stop. Low tire pressure on one tire overloads the other tires on that axle. That is how a short trip turns into a blowout.

Replace trailer tires that fail the tread, the sidewall, or the age guidance from their maker. Replace them as a set when the tires are the same age and one of them is done. Mixing one new tire with three older tires on the same trailer makes the new tire do more than its share.

Stored trailer tires need the same walk. Tires stored outside crack sooner. Tires stored under a cover still age. Flat spotting shows up as a thump for the first miles after a trailer has been sitting. Tire covers slow the sun. They do not reset the date code.

Passenger vehicle tires are the wrong fix for a trailer axle. Trailer tires are built for a heavy load that sits, then rolls. Car tires are built for a car. If you are unsure which tires are on the trailer, read the sidewall and the placard before you buy the next set.

Tread, cracks, and load still come first

A young tire can be done. NHTSA’s reasons to stop using a tire include tread worn down to the penny test, cuts, cracks, bulges, and irregular wear from low pressure or overloading. Trailer tires see long sits and then a heavy load. Low pressure on a loaded trailer is a common way to ruin a tire that still shows a fresh date code.

Use the tire placard on the trailer for size and tire pressure, not the number printed as a maximum on the sidewall. Check tire pressure cold, before the highway miles. The spare tire ages even when it never rolls. NHTSA says spare tires are easy to forget for that reason. Uneven wear on the tires usually means tire pressure, load, or an axle issue, not a mystery.

Here is the short version of the tire life check. Read the age on the tires. Look for wear on the tires. Look for cracks on the tires. Compare the tires with the placard. Then decide if you replace the tires or send the trailer out. Good tread on old tires is not a free pass. Fresh tires with a cut still come off. The life of the tires is the shorter of age, wear, and damage.

Weight matters as much as age. If you are matching a trailer to a truck, the GVWR vs payload guide explains why the scale reading and the hitch share the load. Hitch style changes the truck setup, which is covered in the bumper pull vs gooseneck guide.

A simple way to decide

Read the DOT date on every tire, including the spare. Look for cracks, bulges, and uneven wear. Confirm the pressure and the load against the trailer placard. If the tires are in the 6 to 10 year window your manufacturer talks about, or if you cannot tell when they were mounted, have them inspected before the next loaded trip.

Come see it in person

Carl’s Trailer Sales can look at the tires with the rest of the trailer at 10958 US HWY 212, Belle Fourche, SD 57717. Service is listed at trailer service and repair. If you are shopping a different trailer, start with trailers for sale in Belle Fourche. Call (605) 892-4032.

When to replace the tires

Replace trailer tires for tread wear, for dry rot, or for a date code that has reached the window your tire maker publishes. One flat tire is a reason to inspect the other tires, not a reason to ignore them. A cut in the tire tread or the tire sidewalls means that tire is done.

Miles are a clue. Life is the combination of miles, storage, and load. Rubber that looks chalky has been in the sun. Tire covers help stored tires. They do not stop age. Load range on the sidewall has to match the placard. The wrong tires on a trailer axle are a towing problem and a safety problem.

How long do trailer tires last if you do the walk every season? Longer than tires you never look at. Tires last when pressure is right, the load is right, and you replace them before the sidewall gives up. A blowout on the highway is the expensive way to learn the date code.

Frequently asked questions

How do I tell how old a trailer tire is?

Find the DOT number on the sidewall. The last four digits are the week and year it was built. A code ending in 0921 was built in the ninth week of 2021. Check both sides. The full number may be on only one sidewall.

Do I have to replace trailer tires at six years?

Not by federal law. NHTSA says some manufacturers recommend replacement between 6 and 10 years. Goodyear’s RV guidance says to replace RV tires that have been in service 6 years or more. Bridgestone says to remove tires at 10 years and inspect them after five. Follow the maker of the tire on your trailer.

Can trailer tires with good tread still be unsafe?

Yes. Age, cracks, bulges, and damage from low pressure or too much weight can finish a tire before the tread is gone. NHTSA lists those as reasons to stop using a tire.

Does the spare tire count?

Yes. Spares age even when they are not used. NHTSA and Bridgestone both tell you to include the spare when you check age.

Can Carl’s check my trailer tires?

Yes. Bring the trailer to Carl’s Trailer Sales in Belle Fourche for service, or ask when you are looking at inventory. We can help you match the date codes to the load the trailer is rated to carry.