Most flat tyres are preventable. Blowouts are caused by excessive flex in underinflated tyres. They overheat and let go, basically. Solution? Simple – check your tyre pressures every two weeks. The recommended pressure is on the car’s tyre placard, usually located inside one of the front door frames.
Location, Location, Location
Most flat tyres are unscripted – you don’t choose where or when they occur. Andrew Ticker, a technical specialist for Mercedes-Benz and veteran mechanic of 22 years says you should never attempt to change a flat tyre if you’re stopped close to the prevailing traffic flow. “Drive slowly [read: jogging pace] to an area where you can pull safely off to the side,” he advises. “Don’t worry about damaging the tyre – your safety is more important than that.”
No, really. Check it out, if only to identify anything quirky about your car – such as whether your car has a space-saver spare tyre (these thinner spares are increasingly prevalent and often speed-limited to 80km/h.)
The standard toolkit usually boils down to a jack plus a socket wrench for the wheel nuts. If you can’t find them ... use the owner’s manual. (Andrew Ticker says it’s a great idea to verify the presence of your car’s toolkit before you’re actually face to face with a flat.)
Air in There?
Futility, squared: it’s very frustrating when you find that the spare tyre is flat. Tyres often leak slowly, which is why you must check the pressures – in all five of your tyres – regularly.
Get Tooled Up
Flat tyres aren’t uplifting experiences, but you can improve your lot if you add a reflective safety vest to make you more visible at the roadside, plus a cheap plastic tarp that’ll separate haute couture from the dirt/mud at the roadside, a 20cm-long block of wood to chock the wheels, and an LED torch on a headband so you can see what you’re doing and still have both hands free to work (dorky, perhaps, but invaluable if you break down after dark in the boonies).
Life & Limb
Andrew Ticker advises: “Never – repeat, never – poke any part of your body under a car that is supported only by a jack. Cars are totally unforgiving if they fall on you, and a minor slip is all it takes.” Squat down to the side of the flat rather than, say, sit down with your legs under the car.
Loosen the wheel nuts before you start jacking. It’s much easier to exert leverage with the car’s weight holding the wheel steady.
Andrew Ticker’s basic procedure for changing the tyre, subject to the peccadilos of individual owner’s manuals:
- Move the car safely away from the traffic flow, find a flat, level and stable spot, activate the hazard lights, apply the handbrake and select ‘P’ (or first gear in a manual). Get the passengers out and move them safely away from the roadside.
- Locate the tools and the spare, and set them down near the flat.
- Chock the wheel diagonally opposite the flat tyre, place your block of wood snugly behind the tyre as a physical barrier to the car rolling off the jack.
- Undo the wheel nuts half a turn – before jacking the car.
- Place the jack under the jacking point (see owner’s manual) and jack the car until the flat tyre lifts free.
- Remove the wheel nuts, and gently slide the flat tyre off the studs.
- Grab the spare, turn it so the holes are in the same orientation as the studs, then lift and slide it on. Then fit the wheel nuts, finger tight.
- Lower the jack, then nip the nuts tight using the wrench. Do every second nut in sequence, twice (just to be sure).
- Stow everything back in the car, double check you haven’t left anything behind, and drive smoothly off, paying close attention for the first kilometre or so that the car drives normally.
10. Last – but definitely not least – get the flat tyre repaired or replaced at the earliest opportunity.
One final tip: Ticker says you should give this a go in the driveway at home if you’ve never had to do it in the field. And, when you do it in the field, don’t rush.