How Old Is Too Old for an Unused Spare Tyre?

Here is the uncomfortable truth about the spare in your boot: it could be twenty years old. If it is the original spare that came with a used car, it may well be older than some of the kids in the back seat. Tread depth tells you nothing here — a spare can have 100% tread and still be unsafe, because the enemy is not wear, it is age. Rubber is a perishable material, and a tyre that has never turned a kilometre still gets old.

Do spare tyres expire if they are never used?

Yes. Rubber compounds oxidise and lose flexibility over time whether or not the tyre is driven. The oils that keep the rubber supple slowly migrate out, the tyre hardens, and tiny cracks form — the same process behind UV damage and dry rot and sidewall cracking. A hardened, cracked spare has less grip and is far more likely to fail under the load and heat of highway speeds, which is exactly when you are relying on it.

This is the same ageing question that applies to your road tyres, covered in do tyres expire: shelf life vs road life. The difference is that a spare gets no exercise to flex the rubber and no regular inspection — so it tends to be both older and in worse condition than anyone expects.

How do you work out how old a spare tyre is?

Read the DOT date code. The last four digits of the DOT stamp on the sidewall give the week and year of manufacture — for example, 2419 means the 24th week of 2019. If you can only find a three-digit code, the tyre was made before 2000 and should have been replaced long ago. Our full walkthrough is in how to read the DOT date code.

Check both sides — the full code is sometimes only on the inner sidewall, which on a spare you can simply roll over to read.

At what age should you replace an unused spare?

There is no single legal number in Australia, but the industry consensus is clear enough to act on:

Age from DOT date	What to do
0–5 years	Generally fine. Keep it inflated and stored out of sun and heat.
5–10 years	Inspect at least yearly for cracking, hardening and deformation. Many makers advise replacing from here.
10 years +	Replace regardless of tread or appearance. Treat it as emergency-only even before that.

These are guide figures for 2026, consistent with the advice we give for replacing tyres over five years old. Several manufacturers recommend yearly expert inspection from five years and replacement by ten years at the latest, even for a tyre that has never been fitted. Australia has no mandated expiry date, so if your spare is borderline, have a fitter assess it.

Does a space-saver age the same way?

Yes — a space-saver is still rubber and still ages, even though it is small and lightly built. Arguably it matters more, because a space-saver is already a reduced-performance temporary wheel with tight speed and distance limits; an aged one has even less margin. Check its DOT code and its pressure on the same schedule as a full-size spare.

Where the spare lives changes how fast it ages

Location matters. A spare stored under the boot floor, inside the cabin’s climate, ages more slowly than one mounted under the vehicle or on a rear door, where it copes with road heat, UV, water and grime. Externally mounted 4WD spares in particular should be inspected more often and, ideally, given a cover. If you store spare wheels at home, the principles in storing spare tyres and wheels in an Australian garage — cool, dark, dry, away from ozone sources — apply to the one in your car too.

For background on tyre ageing, Carsales’ explainer on whether tyres age and the Bridgestone Australia FAQ set out the same principles, and the Tyre & Rim Association standards sit behind most of it.

Can you still use an old spare in an emergency?

If you are stranded and the only spare you have is older than you would like, fitting it is usually better than driving on a flat or being stuck — but treat it as a limp-home measure, not a repair. Keep speeds down, avoid hard cornering and braking, watch for any vibration or bulging, and get to a tyre shop as your first stop. An aged tyre’s failure mode is sudden, so the goal is the shortest safe distance to help. The moment you are off the roadside, replace it: an old spare that has “done the job once” has not earned another trip. Factor its age into your trip planning the same way you would check its pressure — both are easy to forget until the worst moment.

Frequently asked questions

My spare has full tread — is it still safe if it is old?

Not necessarily. Tread depth measures wear, not age. A spare with full tread but hardened, cracked rubber can fail under load and heat. Check the DOT date, not just the tread.

Is there a legal expiry date for spare tyres in Australia?

No. Australia does not set a mandatory tyre expiry date. The 5-year-inspect, 10-year-replace guide comes from manufacturers and industry, not legislation — so confirm a borderline spare with a fitter.

How do I tell how old my spare is?

Find the DOT code on the sidewall. The last four digits are the week and year it was made (e.g. 0320 = week 3, 2020). Older three-digit codes mean a pre-2000 tyre.

Should I replace a 10-year-old spare that has never been used?

Yes, as a guide. Most manufacturers advise replacing tyres at around ten years regardless of use, because the rubber has aged. Treat an older spare as emergency-only in the meantime.

Does an under-car or rear-door spare age faster?

Yes. Exposure to UV, heat and water accelerates ageing, so externally mounted spares should be inspected more often and kept covered where possible.