Flat Tire in San Antonio: What to Do and Where Your Spare Is

Keep a firm grip on the wheel, ease off the gas, and let the car slow down before steering to the right shoulder or the next exit. Turn on the hazard lights. Once stopped, stay belted in if traffic is passing close.

Do not brake hard or swerve; a car with a flat pulls toward that side, and gentle inputs keep it straight. The best place to stop is not always the nearest one. A frontage road, an exit ramp shoulder or a parking lot is far safer than a narrow strip of shoulder on Loop 410, I-35 or I-10, where traffic passes a few feet away. Driving slowly a short distance on a flat can ruin the tire, but a tire is cheaper than a crash. Once you stop, set the parking brake, put the car in park and note the nearest exit, mile marker or cross street before you call anyone.

In most sedans and hatchbacks the spare sits under the trunk floor. Many SUVs keep it under the cargo floor or on the rear door, while pickups and many minivans hang it underneath the vehicle on a cable. Some newer cars have no spare at all.

Lift the trunk or cargo floor panel first; the spare is often under a cover with the jack in a foam tray beside it. On pickups, the spare usually hangs under the bed near the rear bumper and is lowered by turning a crank rod through a small hole above or behind the license plate. Minivans often use the same cable system under the middle of the vehicle, with the access in the floor between the front seats or behind them. Some SUVs mount it on the rear door. If you find a compressor and a bottle of sealant instead, the car came with an inflator kit. The owner's manual has a section on flat tires with a diagram for your exact model.

The jack and lug wrench are usually in the trunk or cargo area, in a side panel or a tray beside the spare. On many pickups they sit behind or under the rear seat. The wheel lock key, if the car has one, is often stored with them.

Factory jacks are small scissor or bottle jacks with a folding handle, and they only work safely at the lift points marked on the car's frame, usually notched pinch welds just behind the front wheels and ahead of the rear wheels. Look in the side panels of the trunk, under the rear seat cushion, or in a pouch with the tool kit. If the jack is missing, which is common on used cars, do not improvise with rocks or bricks. A missing jack, a missing wheel lock key or a missing crank rod for an underslung spare are all good reasons to call for help instead of trying to change the tire with what you have.

Run-flat tires let you keep driving slowly for a limited distance after a puncture, so drive carefully to a tire shop or a safe spot. With no spare and a regular tire, a nail in the tread can often be plugged where you stopped.

Cars with run-flats usually have a warning in the dash and a printed limit on how far and how fast you can go on a deflated tire, often around 50 miles at no more than 50 mph, though it varies by tire and car, so check the manual. Many run-flats should be replaced rather than repaired after being driven flat. Cars with no spare and no run-flats rely on an inflator kit. Sealant can get you moving after a small puncture, but some tire shops charge to clean it out. A roadside plug is the other option when the damage is a nail or screw in the tread. A cut sidewall or a shredded tire with no spare means a tow to a tire shop.

Driving a short distance at low speed with the hazards on is often safer than stopping on a narrow highway shoulder. It will likely ruin the tire and can damage the wheel, so go only as far as the first safe spot, never miles.

A fully flat tire flexes so much that the sidewall overheats and breaks down quickly, and the rim can be bent by potholes or curbs. That is a fair trade when the alternative is changing a tire with traffic passing inches away on I-35 at night. At walking or slow speed, with the hazards on, roll to the end of the ramp, a frontage road or a gas station. If the tire comes apart or the steering feels wrong, stop where you are. Never drive on a flat to avoid a tow bill over long distances; the wheel and suspension repairs cost far more than the call.

A tire that is low but still holds its shape usually has a slow leak, often from a nail in the tread, and can often be aired up and plugged. A tire that is fully flat, cut, bulging or coming apart needs the spare.

Walk around the car and compare the tires. A low tire looks soft at the bottom; a flat one sits on the rim with the sidewall folded. Look along the tread for a nail or screw head, and listen for a hiss. Construction zones around the loops leave plenty of debris, so a screw in the tread is a common find. If the tire pressure light is on but nothing looks wrong, use a gauge at a gas station before deciding. Damage in the sidewall, a bubble on the side or exposed cords mean the tire cannot be fixed and should not be driven on at speed, even if it still holds some air.

Call when the car is on a highway shoulder, the spare or jack is missing, a lug nut will not budge, it is dark or very hot, or anyone in the car needs care. Also call if you simply are not sure how to do it safely.

Changing a tire is simple on a flat driveway with the right tools and plenty of light. It gets risky fast on a slope, on soft ground, beside traffic or in the full sun on a San Antonio summer afternoon. A roadside operator brings a floor jack and an impact wrench, works from the side away from traffic where possible, and can plug a tire instead of mounting a spare when the damage allows it. Before calling, find the spare, the jack and the wheel lock key if you can, and note which tire is flat. Those three details let the operator plan the job on the call and quote it accurately.