Why You Should Never Overtake a Turning Truck
One of the most dangerous mistakes a driver can make — especially a learner or newly licensed driver — is trying to overtake a truck, bus, or any long vehicle that's turning. It looks like an easy shortcut. It almost always ends badly. Here's exactly why, and what you should do instead.
The Problem: Off-Tracking
Long vehicles don't turn like cars. When a truck or bus turns a corner, its rear wheels follow a tighter path than its front wheels. This is called off-tracking, and it's the key reason overtaking a turning long vehicle is so dangerous.
💡 Think of it this way: the front of the truck turns the corner, but the back swings wide — sometimes across multiple lanes. What looks like a safe gap on the left side of the truck can disappear in an instant.
The "Blind Side" Danger
Trucks and buses have enormous blind spots — particularly on the right side (the passenger side) and directly behind. When a truck driver signals a left turn and begins turning, they are focused on their own path and mirrors.
If you're beside a truck attempting to overtake on its left as it turns left, you are:
- 🚫 In their blind spot — the driver can't see you
- 🚫 In the sweep zone — the rear of the truck swings through where you're sitting
- 🚫 With nowhere to go — kerb on one side, truck on the other
What Actually Happens
Scenario: You're driving behind a semi-trailer at an intersection. The truck signals left and starts turning. You think "plenty of room" and pull out to overtake on the left.
The truck's cab clears the corner. But the trailer — 15, 20, maybe 25 metres long — keeps swinging. The rear of the trailer clips your car, or pins you against the kerb. The driver never knew you were there.
This type of crash is sometimes called a "swept path" accident. They're disproportionately fatal for the smaller vehicle's occupants because of the sheer mass difference.
The Same Risk Exists on the Right
You might think overtaking on the right is safer — you can see the driver's face in the mirror. But trucks turning right swing across the left lanes, meaning:
- 🚫 The truck occupies multiple lanes as it turns
- 🚫 You may be in a lane the driver thinks is clear
- 🚫 Right turns often mean the driver is watching oncoming traffic, not you
What You Should Do Instead
- ✅ Wait behind — Give the truck plenty of room. If the intersection is clear, the truck will move through and you can proceed once it's clear.
- ✅ Never squeeze past — If there's a gap between the truck and the kerb, it's not for you. That gap is the truck's own swing path.
- ✅ Watch the trailer, not the cab — The cab clears first. Keep watching until the trailer has fully turned.
- ✅ Give extra space on highways — Trucks changing lanes on freeways have the same off-tracking issue at scale.
- ✅ Use your indicators as a cue — If a truck signals and starts to slow before an intersection, that's your signal to hang back.
Know the Dimensions
🚛 Semi-Trailer
Up to 20m long. Rear wheels can swing 2–3m wider than the cab's path on a tight turn.
🚌 Bus
12–18m long. Articulated buses (bendy buses) can be 18–25m. Significant off-tracking on corners.
🚚 Rigid Truck
8–12m long. Less extreme off-tracking than trailers, but still wider than a car.
🚗 Standard Car
4–5m long. Front and rear wheels follow almost the same path. Minimal off-tracking.
The Rule in NSW
Under NSW road rules, you must not drive in the path of an approaching vehicle. But more importantly — even if it's technically legal to be somewhere, if a 40-tonne truck swings into that space, you lose.
The law doesn't protect you from physics. A truck driver who never sees you is not legally in the wrong — but you're still the one in hospital.
The Bottom Line
When a long vehicle is turning, your number one rule is: do not be alongside it. Stay back, watch the full vehicle clear the intersection, and only proceed when the path is completely clear.
Patience at an intersection costs you 10 seconds. The alternative costs far more than that.