20 questions
Towing Questions, Answered
Short answers to what readers ask most, each linked to the page that covers it properly.
Tongue weight and capacity
- What should my tongue weight be?
- Between 10 and 15 percent of the trailer's loaded weight, measured with the trailer loaded the way you actually tow it. Below 10 percent is where sway concentrates; above 15 percent you are overloading the back of the tow vehicle. Read the full guide.
- How do I measure tongue weight without buying anything?
- At a public scale. Weigh the tow vehicle with the trailer hitched and the trailer's wheels off the platform, then weigh it unhitched. The difference is your tongue weight. Read the full guide.
- Does tongue weight count against my payload?
- Yes. The vehicle treats it as cargo, which is why many trucks run out of payload long before they run out of tow rating. Read the full guide.
- Where is my towing capacity written?
- In the owner's manual or the manufacturer's towing guide for your exact configuration. It is not on the door jamb - that carries GVWR, GAWR and the payload placard, which are different limits and usually the binding ones. Read the full guide.
Sway
- My trailer is swaying right now. What do I do?
- Lift off the accelerator, hold the wheel straight, and do not brake hard with the pedal. If you have a brake controller with a manual lever, apply the trailer brakes alone - that pulls the trailer straight. Then stop and move weight forward. Read the full guide.
- Why did it start on the way home when it was fine on the way out?
- The load changed. Emptying a water tank, using supplies stored at the front, or repacking in a hurry all reduce tongue weight. It is a load story, not a hardware story. Read the full guide.
- Will a weight distribution hitch stop sway?
- Not on its own. A plain weight distribution hitch transfers load; it adds no yaw resistance. Several hitches combine both functions, and those are the ones to buy if sway is your complaint. Read the full guide.
Hitches and mounts
- Is a 2 inch receiver always a Class 3 hitch?
- No. A 2 in opening appears on Class 3, Class 4 and some Class 5 hitches. The tube tells you what fits; the label on the receiver tells you what it can pull. Read the full guide.
- What ball size do I need?
- Whatever is stamped on your trailer's coupler - 1-7/8, 2 or 2-5/16 inches. They are not interchangeable even when one appears to fit. Read the full guide.
- How do I work out what drop I need?
- Park the trailer level on its jack. Measure ground to the bottom of the coupler, then ground to the top of the receiver tube. The difference is the drop, less about an inch for the vehicle settling. Read the full guide.
- How do I stop the hitch rattling?
- An anti-rattle pin with a wedge shim takes up the manufacturing clearance between the mount and the receiver. Check the ball nut torque first, because that sounds similar. Read the full guide.
Brakes, wiring and mirrors
- Do I need a brake controller?
- Only if your trailer has electric brakes. Surge-brake and unbraked trailers do not use one. Check whether your vehicle already has a factory controller before buying anything. Read the full guide.
- What gain setting should I use?
- There is no universal number. Set it empirically at about 25 mph using the manual override alone, raising gain until the trailer brakes firmly without locking. Read the full guide.
- Can an adapter give me trailer brakes from a 4-pin?
- No. A 4-way flat has no brake conductor, and an adapter converts shape rather than capability. Electric brakes need a 7-way installation. Read the full guide.
- My brake lights make the turn signals flash. Why?
- Almost always a bad ground. When the ground path has resistance, current returns through another circuit's filament. Clean the ground at the trailer frame first. Read the full guide.
- Do I legally need towing mirrors?
- Most states specify a rearward field of view rather than a particular mirror, and the wording varies. If your trailer is wider than your tow vehicle, you almost certainly need extensions to meet it. Read the full guide.
About this site
- Do you test these products?
- No, and we never write as though we do. There is no test rig and no instrumented data here. Picks come from manufacturers' published specifications and from how each design works. Read the full guide.
- Why are there no prices?
- There is no live price feed on this site, and a stale price is worse than none. Every buy link goes to Amazon, where the current price is shown. Read the full guide.
- How is the site funded?
- Amazon affiliate commission, at no extra cost to you. It is disclosed above the first affiliate link on every page that carries one, under every buy button, and in the footer. Read the full guide.
- Why are there no customer reviews on the site?
- Because this brand has none, and inventing them would be both dishonest and unlawful. Where you see a verdict here, it is an editorial read with its reasoning shown - not a customer rating. Read the full guide.
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