How to Change a Flat Tire

Changing a flat is one of the few car skills everyone should know, and it takes about 20 to 30 minutes the first time. The steps are simple; the part that matters most is doing it somewhere safe and lifting the car correctly. Practice once in your driveway on a nice day, so the first real attempt is not on a dark shoulder in the rain.

Most of this came with your car. Find it before you need it.

• Spare tire (full-size or compact "donut"), with correct pressure.
• Jack and lug wrench, usually under the cargo floor or in a side panel.
• Wheel lock key, if your car has locking lug nuts. It is often in the glovebox or with the jack.
• Owner's manual, which shows the jack points and spare procedure.
• Wheel wedges or a couple of large rocks or bricks.
• Gloves, a flashlight and reflective triangles.
• Optional but useful: a small piece of plywood to support the jack on soft ground, and a tire pressure gauge.

Step 1: Get to a safe spot

• Signal, slow down and pull as far off the road as possible onto flat, firm ground. A parking lot is ideal.
• Turn on your hazard lights.
• Put the car in Park (or in gear for a manual) and set the parking brake firmly.
• Have passengers get out and wait well away from traffic.
• Set out reflective triangles behind the car if you have them.

Step 2: Wedge the wheels

Place wheel wedges against the tire diagonally opposite the flat. Flat on the front left? Wedge the rear right, in front of and behind it if you can. This keeps the car from rolling once it is lifted.

Step 3: Loosen the lug nuts (on the ground)

1. 1Remove the hubcap or wheel cover if there is one. Some pry off; others are held by the lug nuts themselves.
2. 2Fit the lug wrench onto each nut and turn counterclockwise about half a turn to one full turn. Do not remove them yet.
3. 3If a nut is very tight, put the wrench handle horizontal and press down with your foot, using your body weight. Never use the jack to get extra leverage.
4. 4If your car has a wheel lock, use the lock key on that nut.

Loosening first, while the tire is on the ground, keeps the wheel from spinning.

Step 4: Jack up the car

1. 1Find the jack point in your owner's manual. On most cars it is a reinforced pinch weld just behind the front wheel or just ahead of the rear wheel, often marked by notches or an arrow. Using the wrong spot can bend the body or let the car slip.
2. 2Place the jack on firm, level ground (plywood under it on soft ground or asphalt on a hot day).
3. 3Raise the jack until it meets the jack point squarely, then keep raising until the flat tire is about 2 to 3 inches off the ground. A flat tire needs more clearance than an inflated spare.

Step 5: Remove the flat

1. 1Unscrew the lug nuts fully and put them somewhere they will not roll away, such as the upturned hubcap.
2. 2Grip the tire at the sides and pull it straight toward you. If it is stuck to the hub with corrosion, a firm kick to the sidewall usually frees it (keep the car stable and your body clear).
3. 3Lay the flat on its side, under the car's side sill next to the jack, as an extra precaution.

Step 6: Mount the spare

1. 1Line up the holes in the spare with the wheel studs (rotate the spare to match).
2. 2Push it fully onto the hub until it sits flat.
3. 3Thread each lug nut on by hand, with the tapered or cone side facing the wheel, until snug. Hand-threading avoids cross-threading.
4. 4With the wrench, snug the nuts lightly in a star (crisscross) pattern: tighten one, then the one roughly opposite, and so on. This centers the wheel evenly.

Step 7: Lower the car and torque the nuts

1. 1Lower the jack until the tire carries the car's weight, then remove the jack.
2. 2Tighten each lug nut fully, again in a star pattern, pushing firmly on the wrench.
3. 3Go around once more to make sure each is tight.

Lug nut torque specs vary by vehicle. Many passenger cars fall roughly in the 75 to 100 lb-ft range, and trucks and SUVs often higher; your owner's manual lists the exact figure. Have the torque checked with a torque wrench as soon as practical, and recheck after the first 50 to 100 miles, since nuts can settle.

Step 8: Stow everything and check the spare

• Put the flat, jack, wrench and wheel lock key back in the car.
• Check the spare's pressure as soon as you can; spares often lose air sitting unused. Compact spares typically need around 60 psi; the correct pressure is on the spare or the door placard.
• Pick up your triangles and wedges.

Compact spares are temporary. Their exact limits are printed on the tire or a label on the wheel, and in your owner's manual.

Drive gently, leave extra following distance, avoid hard cornering, and get the original tire repaired or replaced promptly. On AWD vehicles, extended driving on a smaller spare can stress the drivetrain; check the manual.

If your car has no spare:

1. 1Check that the puncture is in the tread, not the sidewall, and is small (for example, a nail or screw). Leave the object in place.
2. 2Follow the kit's instructions exactly: typically connect the sealant bottle to the valve, plug the compressor into the 12-volt socket, and inflate to the placard pressure.
3. 3Drive a few miles at low speed to spread the sealant, then recheck pressure.
4. 4Get to a tire shop soon. Tell them you used sealant, since it must be cleaned out and some TPMS sensors need cleaning or replacement afterward.

Many tread punctures up to about a quarter inch can be repaired properly, using a combination plug-patch from the inside of the tire. A tire usually cannot be repaired safely if:

• The damage is in or near the sidewall or shoulder.
• The puncture is larger than the shop's repair limit.
• The tire was driven on flat for a distance, which can damage the internal structure.
• The tread is already near the replacement point; see how to check tire pressure and tread depth.

If replacing one tire on an AWD vehicle, ask the shop to compare tread depth on all four; some systems require closely matched tires. Use our tire size calculator to decode your size and load rating, and check for tire recalls on our recalls pages.