Check your spare tyre pressure and condition, make sure the jack, wheel wrench and locking wheel nut key are all there and work, and practise finding them — ideally every few months and always before a long trip. Many compact spares need a much higher pressure than your normal tyres, often around 60 psi, which is printed on the spare or in the manual. The change itself is covered in how to change a flat tire safely.
Where Everything Lives
Locations vary: under the boot floor, under the rear of the car on a winch cable, behind a panel, or on the tailgate. The jack and wrench are usually in the same compartment, and the locking wheel nut key often hides in the glovebox or under a seat. Some newer cars have no spare at all and carry a sealant and compressor kit instead. Look up the exact arrangement for your car in the manual, then physically find each item once, in daylight, at home.
The Checklist
- Spare tyre pressure. Check it with a gauge — see how to check tyre pressure correctly. A temporary compact spare is often inflated to around 60 psi; a full-size spare matches the other tyres. Use the figure on the sidewall or in the manual.
- Spare condition. Look for cracks, bulges and dry rot, and check the age using the DOT date code — see how to read a tyre sidewall and how often to replace tyres. Spares often outlive their safe life because they never wear.
- Tread. A full-size spare should meet the same standard as the others — see how to check tyre tread depth.
- The jack. Check it is present, extends smoothly and isn’t rusted or bent.
- The wheel wrench or lug wrench. Make sure it fits your wheel nuts or bolts.
- The locking wheel nut key. If your wheels have locking nuts, confirm the key (adapter) is in the car — without it you can’t remove the wheel.
- Tyre sealant and compressor kit (if you have one instead of a spare). Check the expiry date on the sealant and that the compressor works.
- Extras. A torch, gloves, a reflective vest, a warning triangle and wheel chocks make the job safer.
Lift the spare out, locate the jacking points in the manual and find where the key is stored. Doing it at home takes ten minutes and removes most of the stress of a roadside change.
After You Use the Spare
- Check lug nut torque after about 50 miles, as the nuts can loosen on a new fitting.
- Obey the speed and distance limit on a temporary spare — often about 50 mph — and see how long can you drive on a spare tire.
- Get the original tyre repaired or replaced promptly.
- Check the tyre pressure monitor if it lights up — TPMS light on.
- Refill and restore the kit so everything is in place for next time.
Never work under a vehicle supported only by a jack. Use axle stands on firm, level ground, chock the wheels that stay down, and leave the car in gear or Park with the handbrake on. A jack lifts; stands hold.
Possible Costs
| Item | Typical cost |
|---|---|
| Tyre pressure gauge | $5 – $20 |
| Replacement jack or wheel wrench | $25 – $100 |
| Replacement locking wheel nut key | $30 – $150 |
| Sealant and compressor kit | $30 – $80 |
| New spare tyre | $80 – $250 |
Can I Rely on an Unchecked Spare?
Not really. An old, flat or damaged spare, or a missing locking nut key, leaves you stranded or unsafe. Check it now, and replace anything perished. If you’re setting off on a long journey, do it first — see how to prepare your car for a long road trip.
When to See a Mechanic
If the spare is aged or damaged, you cannot find the locking nut key, or the jack is worn. A tyre shop can check the spare and fit a replacement. More in our maintenance section.
Frequently Asked Questions
How often should I check my spare tyre?
Every few months, and always before a long trip, since spares lose pressure slowly and age unnoticed.
What pressure should a spare tyre have?
A compact temporary spare is often around 60 psi, while a full-size spare matches your other tyres. Check the figure on the sidewall or in the manual.
Do spare tyres expire?
Yes. They age like any tyre, so check the DOT date code and replace one that is cracked or very old.
What if I’ve lost my locking wheel nut key?
Contact the dealer or the key’s manufacturer for a replacement. A tyre shop may be able to remove the nut, but it can damage the wheel.
Can I use sealant instead of a spare?
Many new cars carry a sealant kit. It can seal small tread punctures but not sidewall damage, and the sealant expires.
