How to Change a Flat Tire Safely: Step-by-Step Guide

Move out of traffic, stop on firm level ground, switch on hazard lights, apply the parking brake and read the vehicle owner’s manual before lifting the car. If the road, weather, visibility or ground is unsafe, do not attempt the change. Call roadside or emergency assistance.

A tire change looks mechanical, but the largest risk can be the passing vehicle, unstable jack or incorrect lifting point. NHTSA emphasizes tire maintenance and the owner’s manual because tire size, spare type, rotation rules and vehicle equipment differ.

Decide whether the location is safe enough

Do not work where your body will be exposed to moving traffic. A narrow shoulder, curve, hill crest, bridge, tunnel, soft ground or poor visibility is a reason to seek assistance.

If the tire loses pressure while driving:

1. hold the steering wheel firmly
2. avoid sudden braking or steering
3. reduce speed gradually
4. signal and move to a safer location
5. stop as far from traffic as practical

Follow local rules for warning triangles or other roadside equipment. Do not stand behind or directly in front of the vehicle where another vehicle could push it into you.

If you cannot reach a safe location, call emergency services or road assistance and follow their instructions. Remaining inside with the seat belt fastened may be safer in some traffic environments; in others, moving behind a barrier may be safer. The scene determines the choice.

Check the vehicle and equipment

Find the owner’s manual. It identifies:

• approved jacking points
• jack operation
• spare location and removal
• wheel-lock key location
• lug-nut tightening sequence
• torque specification
• temporary-spare limits

Typical equipment includes the vehicle jack, lug wrench, spare tire and wheel-lock key. Useful additions include gloves, reflective vest, flashlight, wheel chock, pressure gauge and torque wrench.

Inspect the spare before an emergency. NHTSA notes that spares age and can be underinflated because they are rarely used. The required pressure is usually listed on the tire or vehicle label and may be higher than the normal road tires.

Some vehicles have no spare. They may use run-flat tires, a sealant kit or roadside assistance. A sealant kit cannot repair every puncture, sidewall damage or wheel damage.

Prepare the vehicle

1. Select Park in an automatic or a low gear in a manual.
2. Apply the parking brake.
3. Switch off the engine.
4. Turn on hazard lights.
5. Keep passengers away from traffic.
6. Place a chock against a wheel diagonally opposite the flat when available.
7. Remove the spare and tools before raising the vehicle.

Removing the spare first prevents you from reaching into the trunk while the vehicle is supported by the jack.

Loosen the lug nuts before lifting

Remove the hubcap if it blocks the fasteners. Fit the wrench fully on the first lug nut. Turn counterclockwise to loosen it about a quarter to half turn. Do not remove it.

Loosen all fasteners while the wheel remains on the ground. The ground prevents rotation and the vehicle is stable enough to resist the initial force.

If a nut will not move, do not jump on the wrench or use an unsafe extension. An incorrectly fitted wrench can round the nut. Roadside assistance is safer than a damaged fastener or fall.

A locking lug nut requires the matching key. Store the key in a consistent vehicle location, not at home.

Position the jack at the specified point

The correct point is vehicle-specific. It may be a reinforced pinch weld, frame point or marked pad. Do not guess from appearance. Plastic rocker trim and floor panels cannot support the vehicle.

Place the jack on firm, flat ground. A thin board under the jack can improve stability on some surfaces, but improvised blocks can slip. Never use loose stones or stacked objects.

Raise the vehicle until the flat tire is just clear of the ground. Do not put any part of your body under a vehicle supported only by the emergency jack. The jack is for changing a wheel, not for under-vehicle work.

Remove the flat tire and install the spare

Remove the loosened lug nuts and place them where they cannot roll away. Hold the wheel at the sides and pull it straight toward you. It may be heavy.

If the wheel is stuck by corrosion, do not crawl beneath the vehicle or strike it in a way that destabilizes the jack. Seek assistance if a controlled method described by the manufacturer does not release it.

Align the spare with the studs or bolt holes and push it fully against the hub. Install the fasteners by hand. They should turn several threads easily. If one binds immediately, stop and realign it; forcing a cross-threaded nut can damage the stud.

Tighten the nuts by hand in a star or cross pattern. The sequence distributes the wheel evenly against the hub.

Lower and tighten in stages

Lower the vehicle until the tire touches the ground and cannot rotate, but most weight is not yet fully loaded if the manual recommends staged tightening. Snug the fasteners in the specified cross pattern.

Lower the vehicle completely and remove the jack. Tighten to the manufacturer’s torque specification with a torque wrench as soon as possible. Too little torque can allow movement; excessive torque can damage studs, nuts or wheels.

Do not rely on “as tight as possible.” Correct torque is a measured vehicle-specific value.

Reinstall the hubcap only if it fits the spare. Store the flat tire, jack, wrench, wheel-lock key and warning equipment securely.

Temporary spare tires are not normal tires

A compact temporary spare may have a speed and distance limit. Read the sidewall and owner’s manual. It can change braking, cornering, traction, ground clearance and operation of driver-assistance systems.

Check its pressure immediately when possible. Drive directly to a repair facility. Do not use the temporary spare as a long-term substitute, and do not place it on an axle position prohibited by the manufacturer.

A full-size spare can also differ in age, tread and pressure from the installed tires. The vehicle may require matching tire sizes or tread conditions, especially with all-wheel drive.

After the change

Stop if you feel vibration, pulling, noise or looseness. Have the wheel torque checked according to the vehicle or wheel guidance. Repair or replace the damaged tire promptly and return a safe, inflated spare to the vehicle.

Inspect why the tire failed. A puncture, underinflation, impact, worn tread, damaged valve or aging can require different action. NHTSA advises monthly pressure and tread checks and replacement when physical damage or unsafe wear is present.

Never repair a sidewall puncture with a simple plug. A qualified tire professional should inspect the tire internally and determine whether repair is permitted.

Prepare before the next flat

Practice locating the jack points and tools without lifting the car. Check the spare pressure monthly with the road tires. Confirm that the wheel-lock key is present. Add reflective and lighting equipment appropriate to local law.

A five-minute inspection at home is safer than discovering a missing key on an unlit road.

Frequently asked questions

Is it safe to change a tire on the highway shoulder?

Often it is not. If traffic, visibility, slope, ground or weather makes the location unsafe, remain protected in the vehicle when appropriate and call roadside or emergency assistance.

Should I loosen lug nuts before using the jack?

Yes. Break them loose slightly while the tire is still on the ground, without removing them. This prevents the wheel from rotating while force is applied.

Where should the jack go?

Use only the jacking point identified in the vehicle owner’s manual. The correct point differs by model, and lifting on body panels or the wrong structure can cause damage or collapse.

How tight should lug nuts be?

Use the manufacturer’s torque specification and a torque wrench as soon as possible. The value differs by vehicle and wheel. Tighten in the sequence specified by the manual.