A flat tire on the highway is a situation where the next few decisions matter. Pulling over safely, knowing where the equipment is, and following the correct sequence — particularly jack placement — determines whether the tire change goes smoothly or creates a second problem.
This guide covers the complete process from recognizing the flat to getting back on the road, including what to do if your vehicle does not have a spare. This is part of the Total Ownership Guide.
When You Realize You Have a Flat
Don't brake suddenly or overcorrect. A flat tire causes the vehicle to pull toward the affected side. Keep both hands on the wheel, ease off the accelerator gradually, and allow the vehicle to slow naturally. Signal and move to the shoulder or the nearest safe exit.
Get as far off the road as possible. The farther from active traffic, the safer the tire change. On a highway, take the next exit if you can reach it safely — a flat tire can be driven on slowly for a short distance to reach a safer location. Driving on a flat damages the tire and possibly the rim, but both are replaceable; traffic exposure is the more immediate risk.
Turn on hazard lights as soon as you begin to pull over.
On the shoulder: Pull as far right as possible. If you are on a highway shoulder with fast-moving traffic, consider whether it is safer to wait for roadside assistance rather than change the tire yourself. A tire change in active traffic lanes is genuinely dangerous.
Before You Jack: Safety Setup
- Apply the parking brake
- If you have wheel wedges or rocks, place them against the tires on the opposite end of the vehicle from the flat — prevents the vehicle from rolling
- If you have reflective triangles or road flares, place them 10–15 feet behind the vehicle
- Turn on hazard lights (confirm they are still on)
Locating Your Equipment
Spare tire: In the trunk (usually under the trunk floor panel), under the vehicle bed (many trucks and SUVs — look for a cable mechanism at the rear), or mounted externally on the rear of the vehicle (some SUVs and trucks).
Jack and lug wrench: Typically stored with the spare — under the trunk floor panel or in a dedicated storage pocket. Some vehicles store the jack in the engine compartment.
If you are not sure where the spare or jack is located: Check the owner's manual — every vehicle specifies spare and equipment locations.
Check the spare: Before committing to a tire change, confirm the spare is inflated. A flat spare discovered after the wheel is already off is a worse situation than calling for roadside assistance from the start.
Step-by-Step: Changing the Tire
Step 1: Loosen the Lug Nuts Before Jacking
With the vehicle still on the ground, position the lug wrench on the first lug nut and turn counterclockwise. Break each lug nut loose — one full turn, no more. Do not remove them yet.
Why first: Once the vehicle is jacked, the tire can spin freely when you apply torque. Loosening the nuts while the tire is on the ground prevents this.
For tight lug nuts: Position the wrench at the 9 o'clock position and use body weight pressing downward. Do not use a cheater bar or extension on a factory lug wrench — this risks rounding the nuts.
Step 2: Find the Jack Point
This is the most important step to get right. Jacking at the wrong point bends or cracks the vehicle's rocker panels or undercarriage components.
Every vehicle has designated jack points — reinforced areas of the frame or unibody designed to accept the jack load. They are typically indicated by:
- Small notches or triangular marks along the bottom edge of the door sill
- A reinforced flat area visible along the pinch weld (the seam where the body panels meet at the bottom)
For the floor jack included with the vehicle: Position it at the jack point closest to the flat tire.
Owner's manual: Specifies jack points with diagrams. If you are uncertain, check before jacking.
Step 3: Jack the Vehicle
Position the jack under the correct jack point. Raise the vehicle until the flat tire is approximately 6 inches off the ground — enough to remove the flat and install the spare, which is slightly taller than a fully flat tire.
Never get under a vehicle supported only by a floor jack. The scissor jack included with most vehicles is designed for tire changes only — not for any undercarriage work.
Step 4: Remove the Flat Tire
Remove the lug nuts completely — keep them together in a pocket or the wheel well. Pull the flat tire straight toward you and set it aside flat (do not lean it against the vehicle where it can roll into traffic).
Step 5: Mount the Spare
Lift the spare onto the wheel bolts, aligning the holes with the studs. With the spare seated on all studs, thread the lug nuts by hand until finger-tight.
Step 6: Tighten the Lug Nuts (Star Pattern)
With the vehicle still jacked, tighten the lug nuts in a star or cross pattern — not in a circle. The star pattern ensures the wheel seats evenly against the hub:
For a 5-lug wheel: tighten lug 1, then the one directly across (lug 3), then lug 5, lug 2, lug 4.
Tighten firmly by hand with the lug wrench, but do not fully torque yet — the tire can still spin.
Step 7: Lower the Vehicle and Final Torque
Lower the jack until the spare is fully on the ground bearing the vehicle's weight. Remove the jack. Now apply full torque to the lug nuts in the same star pattern — use body weight on the wrench.
Correct torque: 80–100 ft-lb for most passenger cars. If you have a torque wrench, use it. If not, firm body weight on an 18-inch wrench approximates correct torque for most vehicles.
Step 8: Stow the Equipment and Flat Tire
Place the flat tire where the spare was stored. Stow the jack and lug wrench. Do not leave them loose in the trunk — they become projectiles in a sudden stop.
Driving on the Spare
Full-size spare: Same size as the original — can be driven normally until the flat is repaired or replaced. Get the flat assessed and the lug nuts re-torqued at a shop as soon as practical.
Compact spare ("donut"): Temporary use only.
- Maximum speed: 50 mph
- Maximum distance: 50–70 miles (manufacturer recommendations vary — check the spare or owner's manual)
- Do not drive on a highway at highway speeds with a compact spare
- Get the flat repaired or replaced at the earliest opportunity — the compact spare is not designed for sustained use
What If There Is No Spare?
Many newer vehicles are sold without a spare — instead providing a tire inflation kit (a can of sealant and a compressor). Inflation kits work for slow punctures in the tread area but cannot fix sidewall damage, large punctures, or damage from driving on a flat.
If you have an inflation kit: Follow the instructions on the can. Sealant is temporary — the tire needs to be professionally repaired or replaced, and the sealant must be disclosed to the tire shop (it coats the inside of the tire and requires cleaning).
If neither spare nor kit resolves the situation: Roadside assistance (through your insurer, manufacturer's roadside service, AAA, or a phone app service) is the fallback.
Frequently Asked Questions
*All ranges and costs are estimates and may vary.