Step 3 of 13
Flat tyre step 3 of 13: Handbrake on, chock a wheel
Put the handbrake on and leave the car in gear (or in Park). Then wedge a chock against the wheel diagonally opposite the flat, here the rear right, so the car cannot roll while it is up on the jack.
- 1× Wheel chock
Tools: none, just your hands
- No chock? A brick or a big stone against the tyre does the same job.
All 13 steps
- 1Pull over somewhere safe
- 2Warn the traffic
- 3Handbrake on, chock a wheel
- 4Get out the spare and the tools
- 5Loosen the nuts on the ground common mistake
- 6Put the jack under the jacking point common mistake
- 7Raise the car
- 8Take off the nuts and the wheel
- 9Lift the spare onto the studs
- 10Run the nuts on by hand common mistake
- 11Lower it, then tighten in a star common mistake
- 12Lower all the way, check again
- 13Pack up and drive gently
What you need
- Spare wheel · a space-saver here; check its pressure
- Jack and its handle · from the car’s kit
- Wheel brace · with a socket that fits the nuts
- Locking wheel nut key · if the car has locking nuts
- Warning triangle
- Wheel chock · or a brick
- Gloves and a torch · helpful
- The car’s handbook · for its jacking points and nut torque
Questions
Should I loosen the wheel nuts before jacking the car up?
Yes. With the tyre on the ground the wheel cannot turn, so the nuts can be broken loose a quarter turn. Once the car is up, the wheel would just spin with the brace.
Which way do wheel nuts undo?
Anticlockwise, as you face the wheel: lefty-loosey. They tighten clockwise.
Why tighten wheel nuts in a star pattern?
Going across from each nut to the one opposite pulls the wheel evenly against the hub. Going round in a circle can pull it on crooked and leave the last nuts loose.
How tight should wheel nuts be?
To the torque in the handbook, typically around 100 to 140 Nm for a small car. On a 35 cm brace, 110 Nm is a firm push of about 32 kg. Check them again after about 50 km.
How fast can I drive on a space-saver spare?
Usually no faster than 50 mph (80 km/h): the limit is printed on the wheel or the tyre. It is for getting to a garage, not for long journeys.
How far behind the car does the warning triangle go?
In the UK, at least 45 metres (147 feet) behind on the same side of the road, says the Highway Code, and never on a motorway.
Safety
Never get under a car held up only by a jack, and never change a wheel on a motorway or where the traffic passes close: call for help instead. Use the jacking points and the torque in your car’s handbook.
About this guide
This guide shows a typical small hatchback with a space-saver spare. The figures are general ones: 110 Nm is a common wheel-nut torque for a small car (most are somewhere around 100 to 140 Nm), and its wheels are held by five nuts on M12 × 1.5 studs. Your car’s handbook gives its own jacking points, torque and spare-wheel limits; where it differs from this guide, follow the handbook.
The 45 metres for the warning triangle are from the UK Highway Code (rule 274), which also says never to use one on a motorway. The push on the brace is worked out from the torque: 110 Nm on a 35 cm handle is 314 N, the weight of about 32 kg. The clamping force is an estimate for an M12 nut tightened to 110 Nm.
Sources: UK Highway Code, rules 274 to 287 (breakdowns).
The 3D models, drawings and text are our own.