Published by Rims & Tires
Compiled & checked by the site's publisher from manufacturer, NHTSA & USTMA data · Updated 2026-07-24
Your backup plan in a flat-tire situation depends entirely on what your vehicle came with. Some cars ship with a full spare. Others give you a donut, an inflation kit, or nothing more than run-flat sidewalls. Figure out which one you have before you need it, not on the shoulder of the highway at night.
Full-size matching spare
What it is: a fifth tire and wheel that matches your regular tires in size and load rating. On some vehicles it's truly identical; on others it's just close enough to drive on safely.
How long it lasts: indefinitely. It has the same life expectancy as your regular tires. Rotate it into the regular set every other rotation for even wear.
Speed limit: none specific — it is a regular tire.
Best for: trucks, SUVs, older vehicles. Anyone who regularly drives in remote areas where roadside service is not guaranteed.
Downside: heavy, takes cargo space. Many modern crossovers have eliminated it in favor of smaller solutions.
Temporary spare (donut spare)
What it is: a compact spare tire, narrower and smaller than your regular tires, mounted on a smaller steel wheel.
How long it lasts: 50–70 miles maximum before it must be replaced with a proper tire. Not intended for extended use.
Speed limit: 50 mph maximum. Exceeding this risks failure.
Best for: getting you to a tire shop after a flat. Nothing more.
Downside: cannot be used on an AWD vehicle for extended driving (the size mismatch stresses the drivetrain). Must be replaced as soon as possible.
West Georgia Local
Find the right shop near you
Tell us your vehicle and what you need — we'll match you with a vetted West Georgia shop. Free, no obligation.
Run-flat tires
What it is: tires with reinforced sidewalls that support the vehicle's weight even with zero air pressure, allowing continued driving at reduced speed for a limited distance.
How long it lasts after puncture: typically 50 miles at 50 mph or less. That's enough to reach a shop.
Best for: vehicles equipped with TPMS and run-flat OEM tires (BMW, Mini, Cadillac, Mercedes). The benefit: no spare needed, no storage space lost.
Downside: run-flat tires typically cost more than standard tires. After a puncture at zero pressure, the tire is typically destroyed and not repairable. Some run-flat punctures go unnoticed without a working TPMS light, which matters, since FMVSS 138 has required tire pressure monitoring systems on all new U.S. passenger vehicles since the 2008 model year.
Important: don't replace run-flat tires with standard tires on a vehicle that has no spare. Do that and you've got no backup option at all.
Tire inflation kits
What it is: a battery-powered air compressor and a can of tire sealant. No spare tire or wheel at all.
How long it lasts: sealant temporarily seals small punctures (under 1/4 inch). Works for slow-leak punctures; does not work for blowouts, sidewall damage, or large holes.
Speed limit after use: 50 mph maximum; get to a shop within 100 miles.
Best for: manufacturers trying to save cost and weight. Found on many modern compact cars and electric vehicles.
Downside: leaves foam sealant inside the tire that contaminates TPMS sensors and makes the tire non-repairable. Many shops charge $30–50 to clean the sealant out. Does not help with blowouts.
Frequently asked
Can I use a donut spare on an AWD vehicle?
Only for short distances at low speed, just enough to get to a shop. Not for highway driving. The donut's different diameter and rolling circumference can stress AWD differentials, couplings, and transfer cases with extended use. Replace the flat tire as quickly as possible.
What do I do if my car has no spare — just a tire kit?
Use the inflation kit for slow leaks to get to a tire shop. For blowouts or sidewall damage, call roadside assistance. Consider buying a compact spare and wheel that fits your vehicle as an aftermarket safety measure — check your vehicle's spare tire well dimensions.
How do I know which type of spare my car has?
Check the trunk well, under the cargo floor, or beneath the rear of the vehicle, and skim your owner's manual under the flat-tire section. A small skinny wheel is a donut; a full matching wheel is a full-size spare; a little compressor and a can of sealant means you have an inflation kit and no spare at all. Do this in the driveway, not on the shoulder at night.
Should I carry a real spare even if my car didn't come with one?
For a lot of drivers, yes. If you cover rural miles in West Georgia where cell service and roadside help can be thin, a compact spare and a small jack are cheap peace of mind. A tire shop can help you source a spare that fits your wheel's bolt pattern and confirm it clears your brakes.
Keep reading
Last updated 2026-07-24. General guidance only — confirm specifics with a local shop for your exact vehicle.