Skip to content

How to change a flat tire and check tire pressure safely

A flat tire or sudden puncture is one of the most common roadside emergencies. Knowing how to change a tire safely and maintain proper tire inflation prevents accidents, avoids rim damage, and keeps you moving.

Do this now

  1. Park on flat, level ground away from moving traffic (such as a parking lot or wide shoulder). Never attempt to change a tire on soft dirt or a steep slope.
  2. Turn on hazard lights, engage the parking brake firmly, and turn off the engine.
  3. Place heavy rocks, wooden blocks, or wheel chocks behind the tire diagonally opposite the flat tire to prevent rolling.
  4. Locate your spare tire, scissor jack, and lug wrench (usually under the trunk floor mat).
  5. Loosen the lug nuts ½ turn counter-clockwise while the tire is still resting firmly on the ground. Do not remove them completely yet.

Step by step tire replacement instructions

  1. Locate jacking points: Find the reinforced metal notch (pinch weld) on the vehicle frame near the flat tire. Check your vehicle owner manual for exact jack placement notches.
  2. Raise the vehicle: Position the jack under the jacking point and crank clockwise until the flat tire is approximately 5 cm (2 inches) above the ground.
  3. Remove lug nuts and wheel: Unscrew the loosened lug nuts completely by hand and pull the flat tire straight toward you off the wheel hub.
  4. Mount the spare tire: Align the spare tire rim holes with the wheel studs and push the spare firmly onto the hub.
  5. Hand-tighten lug nuts: Thread lug nuts back onto the studs with the tapered end facing inward. Tighten them snug by hand.
  6. Lower vehicle and torque lug nuts: Lower the jack until the spare tire touches the ground slightly, then use the lug wrench to tighten all lug nuts firmly in a star (crisscross) pattern. Lower the jack fully and remove it.

Donut spare tire safety rules

Compact or temporary spare tires ("donuts") differ significantly from standard road tires:

  • Speed limit: Never drive faster than 80 km/h (50 mph) on a compact spare.
  • Distance limit: Do not drive further than 80 km (50 miles) on a temporary spare.
  • Check spare tire pressure: Donut spares require higher air pressure (typically 420 kPa / 60 PSI). Check spare pressure regularly.

Checking and adjusting tire pressure (PSI)

Proper tire inflation extends tire life and prevents blowouts:

  • Locate recommended PSI: Check the sticker inside the driver-side door jamb (not the maximum pressure printed on the tire sidewall).
  • Check pressure cold: Measure tire pressure with a digital or pencil gauge when tires have been parked for at least 3 hours.
  • Inflating at gas stations: Connect the air pump hose to the valve stem, check reading, and inflate in short bursts until reaching recommended PSI.

When to call roadside assistance

Do not attempt a DIY tire change if: - You are stopped on a narrow highway shoulder with fast traffic passing close by. - Lug nuts are rusted or over-tightened and cannot be loosened by hand. - You do not have a functional spare tire or working jack.