Compact spare or full-size spare
Most cars that carry a spare carry a compact one, often called a donut: narrow, small and light, made to save trunk space and weight. Some trucks and SUVs carry a full-size spare that matches the other wheels, though even those can differ in tire type from the set on the car.
You can tell which you have by size and by the sticker. A compact spare usually has a bright label on the wheel or sidewall with its speed and pressure limits printed on it.
Speed and distance
Most compact spares are marked for no more than 50 miles per hour. Distance limits vary by manufacturer and are often in the range of 50 to 70 miles, so read your manual's figure instead of trusting a rule of thumb. Think of the limit as how far the tire can be driven safely, not a distance to aim for.
A compact spare is smaller than the other tires, so the car handles differently. It grips less, braking distances grow, and stability and traction systems can behave oddly because one wheel turns at a different rate. Leave extra room, avoid hard braking, and take it easy in the rain.
Some manuals also say to keep the load light, since a compact spare is rated for less weight than a full tire. A trunk full of luggage or a car full of passengers asks more of it than it was made for, so lighten the load or split the trip if you can.
Check the pressure before you need it
Compact spares often call for a much higher pressure than regular tires, commonly around 60 psi, but the sticker on yours is the number to use. A spare that has sat untouched for years loses air, and a flat spare is no help when you're on the side of the road.
Put a pressure check on the spare on your calendar twice a year. If you've just put it on, check its pressure before you pull away. The number to use is on the spare itself, then in the manual. Any gas station air pump will do, and a small compressor that plugs into the car's power outlet is a cheap thing to keep in the trunk.
Plan the next step before you drive off
Metro Dallas–Fort Worth is big. A drive across it can eat most of a spare's rated distance, so decide where the flat is going before you leave. A tread puncture can often be repaired, which gets you back on a full tire quickly. Anything else means a replacement, and a spare shouldn't stay on the car for weeks.
TRA can do either at your location. A tire repair for a puncture in the tread is $54–$60, and a tire supplied and installed is from $129, plus a $19 dispatch fee charged once per job. Tire availability varies, and dispatch confirms a tire is available before a driver is sent.
Common questions
You can if the speed rating allows it, but many compact spares are marked for 50 mph, well below freeway speeds in DFW. If yours is, stay on slower roads where you can, and keep to the right.
If it matches the other tires in size and type, usually yes, for as long as it takes to repair or replace the flat. Some all-wheel-drive vehicles need all four tires to be nearly the same size, so check the manual.
Then it can't be used, and a spare tire change won't work. We can supply a tire and install it on site instead, which is the tire replacement service.