Highway Passing/Towing Tips

How to Pass Vehicles While Towing a Trailer – Important Data.

Use caution when passing a vehicle while towing a trailer, especially if you are hauling an unbalanced load like a boat or one with loose materials. Ensure the safety of other vehicles on the road. 

According to Ontario’s Ministry of Transportation, half of the reported trailer collisions involve single vehicles, while a further 20% are rear-end collisions.



Where the fault is that of the tow vehicle driver, about 30% of the drivers reported they had “lost control of their vehicle.”Ministry of Transporation / Driver’s Handbook / Towing.


If you’ve ever tried to pass a vehicle while also towing a weighty or awkward load on a trailer, you might have quickly found yourself panicking or, in the worst case, in real trouble trying to control the trailer. There is a lot to consider, including knowing when you should not pass another vehicle on a highway or gravel road. 

Rain, wind, and the sun hitting your eyes just the wrong way make passing even more of a challenge.


Use Standard Axle’s Towing Checklist – prepare your vehicle for safe towing and passing.

Check all of your tires’ pressure, including the trailer tires: 

Read your trailer manual; the trailer tires may often require higher pressure. Rubber hardens with lack of use; even if your trailer tires have lots of tread, months of nonuse can flatten the tire bottoms and moving them can cause that rubber to crack. It can be a good idea to push or pull your trailer to expose a new tire area every month. 

See our selection of our best trailer tires.


Have at least one spare trailer tire:

Have a lug nut wrench specific to the trailer wheels and a jack correctly sized to your trailer, so you don’t get stranded on the side of a road. 


Invest in wheel chocks:

Wheel chocks are heavy-duty composite wedges that are placed in front of and behind your trailer’s tire to prevent movement (rolling away)


Buy trailer/tow mirrors: 

If your trailer is wider than your vehicle, tow mirrors are the best way to ensure you see possible blind spots. Passing is made simpler with tow-mirrors, allowing you to easily see the length of your trailer.


Check all of your trailer lights before leaving:

With a friend, check that all your trailer turn signals, brake lights, running lights, and hazard lights are functioning, and double-check the electrical wire connection from the back of your vehicle to the front of your trailer. Visually assess the condition of the coupling. Corrosion and weather can unwrap tape, and accidental pulls can separate the wires from their connections.


Check your trailer brakes:

When experiencing trailer sway (see the trailer-sway section below), you should avoid braking; allow your vehicle and trailer to slow on their own. However, in extreme cases, use your trailer brake (never your tow vehicle brake). See our trailer brakes.


Have the correct ball mount trailer hitch. Incorrectly sized hitch balls are a primary cause of accidents. Trailers that become unhitched are accident causes:

Your hitch ball must be properly sized. Tongue weight capacity, distance from the hitch pin to the ball centre, and the height of the rise are all measurements and capacities that must be correct. See our hitches, and please call us at (519) 451 1116 for help choosing your trailer hitch.


Use trailer safety chains:

The chains should have enough slack to allow sharp turns but not drag on the ground.

Always cross the safety chains to create a cradle for the tongue. In the case of a disconnection, the tongue is suspended instead of digging into the asphalt.


Consider getting a larger fuel tank for your tow vehicle:

If you are planning to make towing part of a lifestyle change, a larger fuel tank saves time from needing to stop more often to tank up.


Be patient and have a high degree of driver attention. Go slower on the highway because your speed can lead to circumstances you may not know how to rectify. 

Always drive in the far right lane.

When towing something physically longer and less balanced than your vehicle is not an easy thing to do. Add to that the weight of your load and these factors significantly affect how quickly you should try to stop or might be able to. 


Never drive faster than the posted speed limit: 

When towing a loaded trailer, things can go wrong without notice, and you need time to consider what to do if you feel one side of your trailer lifting or shifting out of your lane going around a curve too fast.


You cannot accelerate as fast as you want to: 

Do not attempt a last-minute pass like you might driving a non-towing vehicle. Even vehicles with large engines will take longer to reach a speed.


You cannot slow down as fast as you want to: 

Travelling downhill with a heavy trailer load behind you requires more space between you and the car in front of you for stopping. If your trailer has a gross trailer weight, vehicle and load of 1,360 kilograms (3,000 pounds/lbs) or more, your car must have brakes strong enough to stop and hold the trailer.” – Ministry of Transporation / Driver’s Handbook / Towing.




Only pass when absolutely necessary; stay alert and vigilant: 

Do not pass at all if it is a two-lane roadway; the chances of your trailer going onto a soft shoulder should be avoided: 

Never pass when approaching an incline, and never pass when on a steep descent. The trailer weight will create problems for both scenarios.


Remember your trailer is longer than you might imagine it: 

Accidents are often a result of a driver not correctly allowing for the length of their trailer. Watch the length the whole time while you are passing a vehicle. Make wider turns and take curves at a broader angle to ensure your trailer tires stay on the road.


Use all of your mirrors (more than you would typically):

Passing a vehicle while towing a trailer requires full awareness of everything behind you while you pass. Make sure another car isn’t pulling out to pass at the same time that you are. Use your mirrors when merging back into a lane to check the length of the trailer.


Signal early. Avoid sudden trailer-sway that results from needing to pull back into your lane quickly:

Make sure you are doing everything to alert other drivers early of your pass.


Make small and slow movements with the steering wheel to prevent trailer-careening or trailer-sway: 

Trailer sway is also called the crack-the-whip effect, named after the children’s game where the effect of an initial and quick change in direction is amplified by the length of the chain of hand-holding children, or in this case, your trailer.



Once trailer-sway is happening, it is hard to regain control.

What is trailer-sway?

Trailer sway happens when there is a side-to-side movement of the trailer. There are many names for it; is also called the crack-the-whip effect and fishtailing.


What causes trailer-sway?

Moving your steering wheel too quickly at high speeds, buffetting of passing vehicles, and even windy conditions will cause the trailer to sway. 


Should you brake if you experience trailer-sway?

Never apply your brake; it will only amplify the effect. Keep both hands firmly on your steering wheel and let your foot off the gas. In extreme situations, you should use your trailer brake, not your tow-vehicle brake.



Contact London’s Standard Axle with any of your trailer and axle needs. We are a knowledgeable team here to help you.