The size stamped on the ball
Balls come in 1-7/8 inch, 2 inch and 2-5/16 inch, and the number is stamped on the top of the ball. The trailer's coupler has its own size stamped on it too. They have to be the same number.
Towing
Towing a trailer for the first time
Nobody is born knowing what a 2-5/16 is. This is the whole of what you need before you hook up to anything: what the parts are called, which numbers have to match, and what actually happens on the road when they do not.
None of it is specific to us. It is true of any trailer you hire, borrow off a neighbour or buy secondhand.
The four things
What to check before you go anywhere
Four answers, and all four are readable in a driveway with a phone in your hand. Getting them before you drive out to collect something is the difference between a trip and a wasted afternoon.
How many pins are in your plug
Four flat pins carry the lights and nothing else. A seven-way round plug carries the lights plus the trailer's brakes and, usually, a charge wire. If the trailer has electric brakes and your vehicle has four pins, the brakes have no way to work.
Whether there is a brake controller in the cab
A controller is the box in the tow vehicle that sends power to the trailer's brakes when you press the pedal. It lives in your vehicle, not on the trailer, so it is yours to have or not have.
What your vehicle is rated to pull
The number is on the sticker inside your driver's door. Compare it with the trailer's empty weight plus everything you are putting on it, which is the figure the trailer actually weighs on the road.
The parts
What a hitch actually is
People say hitch for the whole arrangement, and it is really four separate things bolted to each other. Knowing which one is which is most of being able to ask the right question.
- The receiver. The square tube bolted under the back of your vehicle. It is the part that is genuinely part of the truck.
- The ball mount. The bar that slides into the receiver and is held by a pin. It comes in different drops and rises so the trailer can sit level behind different vehicles.
- The ball. The steel ball bolted through the mount. This is the part with a size, and it is the part people get wrong.
- The coupler. The socket on the front of the trailer that closes over the ball. It has its own size stamped into it, and it has a latch that has to be shut and pinned.
The two sizes have to agree. The ball and the coupler are the only pair of parts on this list that must match each other exactly, and they are stamped so you can check it without measuring anything.
The number on the ball
Three sizes, and they look alike
Almost every trailer you will meet takes one of three: 1-7/8 inch, 2 inch or 2-5/16 inch. The widest and the narrowest are under half an inch apart, and at arm's length in a driveway they are hard to tell apart by eye.
So read the stamp instead. It is on the flat top of the ball, and the coupler carries its own on the side or underneath. If the two numbers are not the same, the answer is a different ball, and a ball is a cheap part.
Ball mounts are usually sold without a ball, and plenty of people own two balls for the two trailers they borrow.
Tongue weight
The bit that keeps it straight
Tongue weight is simply how much of the loaded trailer is pressing down on the ball. It is not a setting. It is a consequence of where you put the heavy things.
The figure people aim for is roughly ten to fifteen per cent of what the loaded trailer weighs, and the way to get there is to put the heavy item slightly ahead of the trailer's axle instead of behind it. Too far back and the trailer wags. Too far forward and your steering goes light.
Load it, then look at your vehicle from the side. A tow vehicle sitting level is doing better than any number you can guess at.
Wiring and brakes
What the plug is carrying
Trailer lights are not optional and they are not the only thing in that cable. The pin count tells you what the trailer can and cannot do once it is hooked up.
- Four flat pins. Running lights, brake lights and the two indicators. Nothing else. This is what most cars and small crossovers have.
- Seven round pins. All of the above, plus a wire for electric brakes, plus power for the breakaway battery and anything else on board. Most trucks set up for towing have one.
- A brake controller. Mounted in your cab, within reach. It reads your brake pedal and decides how hard the trailer brakes. A trailer with electric brakes and no controller is a trailer with no brakes.
- A breakaway cable. The thin cable with a pin on the end. It clips to your vehicle, never to the safety chains, and it puts the trailer's own brakes on if the trailer ever leaves you.
Test the lights with somebody standing behind. Brake, left, right, hazards. A blown trailer bulb is invisible from the driver's seat, and it is the single most common thing wrong with a trailer that is otherwise ready to go.
Weight
Two numbers, added together
What your vehicle has to be rated to pull is the trailer's empty weight plus everything you put on it. Not one or the other. A bare utility trailer is a light job for most half-tons and the same trailer with a machine on it is a different question entirely.
Your own number is on the sticker inside the driver's door. The trailer's empty weight and what it is allowed to carry are on its rating plate, usually riveted to the tongue or the frame near the front. Both numbers are printed on the things themselves, which is why neither of us should be guessing at them.
Weight is not the only limit. A long trailer behind a short vehicle is harder to hold straight than the arithmetic suggests, and reversing one is a skill worth practising in an empty lot before you need it at somebody's gate.
Getting it wrong
What actually happens
None of this is written to frighten anybody off. Towing is ordinary, and thousands of people do it on a Saturday without incident. These are simply the five failures that account for most of the ones who do not.
A ball that is too small
A 2 inch coupler will drop over a 1-7/8 inch ball and feel latched. It is sitting on the ball instead of around it, and the first dip in the road lifts it off. Your safety chains are then the only thing attached to your vehicle.
Too little weight on the tongue
The trailer starts to wag behind you, gently at first and then faster, and braking in the middle of it makes it worse. This is what people mean by sway, and it is almost always a load packed too far back.
Too much weight on the tongue
The back of your vehicle squats, the front lifts, and the steering goes light exactly when you need it. Your headlights end up pointing at the trees.
Brakes on the trailer and no controller in the cab
The trailer pushes you through every stop. On a dry road you notice it. On a wet hill you find out how much of your stopping distance was the trailer's job.
Chains hanging straight down, or left off
Crossed under the coupler, they make a cradle that catches the tongue if it ever comes off the ball. Hanging straight, the tongue goes past them and digs into the road.
Before you pull away
The last two minutes
- Coupler latched and pinned, and the jack wound all the way up.
- Chains crossed underneath the tongue, with enough slack to turn and not enough to drag.
- Breakaway cable on the vehicle, and the plug in.
- Lights checked with somebody watching from behind.
- Tire pressures on the trailer, which sits for months and loses air quietly. The pressure is on the sidewall and on the rating plate.
- Lug nuts checked, and checked again after the first fifty kilometres. A trailer wheel that has been off recently is the one that comes loose.
Then pull forward a few metres and brake gently, before you are anywhere near a road. Anything badly wrong announces itself in that first stop.
Still not sure
Send us a photo of your hitch
That is a thirty second conversation and it has saved a lot of wasted trips. A photo of the back of your vehicle tells us the ball, the plug and usually whether you have a controller, and we will tell you straight whether it will work.
If you are looking at hiring one of ours, each trailer's own page lists exactly what it wants and explains how to check each one, with pictures. Those are the numbers that count, and they are on the trailer's page because they differ from trailer to trailer.
Towing questions and rental questions are both answered on the FAQ, under Trailers.
Ask us
Get a price for the job
Tell us what the car is and what it's doing, and we'll come back to you with a price. Texting is the quickest way to get hold of us.
Next opening: Monday. If the car has stopped you driving, say so and we'll work around it.
Weeknights from 5pm
Saturdays & Sundays from 8am
info@peaklineauto.ca
We rent trailers too, from the same driveway. An equipment trailer and an enclosed cargo one.
Or send it over: your number, the car and what it is doing, one question at a time. It takes a minute and we price it from that.