Spare tyre guide: full-size, space-saver or repair kit

The spare in an Indian car is one of three things: a full-size spare on its own wheel, a smaller temporary spare (a space-saver), or no wheel at all but a sealant bottle and compressor. Which one you have decides how far you can drive after a puncture. A full-size spare is a normal tyre and can be driven on like one, provided it is in good condition. A space-saver is for getting to a tyre shop: the common rule in carmakers’ handbooks is no faster than 80 km/h, pumped up to a much higher pressure than your other tyres, and replaced with a proper wheel at the first chance. A repair kit only works on small punctures in the tread. Whatever you carry, it only helps if it is ready: check the spare’s pressure with your other tyres, and check its age, because a spare that has sat in the boot for years can be too old to trust.

The three kinds of spare

Full-size spare

A full-size spare is the same size as the tyres on the road and sits on a wheel that fits the car. It is the most useful kind: you can drive on it at normal speeds and finish your journey. Its weaknesses are the space it takes and the fact that it is easy to forget. Check whether yours is on the same wheel type as the other four; if it is not, you may need different wheel nuts or bolts, which should be kept with the jack.

Space-saver (temporary spare)

A space-saver is a narrow, lighter tyre on a narrow wheel, smaller in diameter than the road tyres. Carmakers fit it to save boot space and weight. Kia’s owner’s manual sets out the rules for its compact spare, and they are a good guide to what to expect from any space-saver:

• Inflate it to 420 kPa (60 psi), far above a normal car tyre.
• Do not drive faster than 80 km/h on it.
• It lowers ground clearance by about 2.5 cm, so take speed breakers and broken patches slowly.
• Do not take the car through an automatic car wash, tow a trailer, or fit snow chains while it is on.
• Do not use more than one space-saver at a time, and do not fit it to any other wheel or car.
• Its tread wears out faster than a normal tyre’s, and continuous use can lead to tyre failure.

Your own car’s figures are printed on the space-saver’s sidewall and in your handbook. Use those.

A repair kit instead of a spare

Since July 2020, the Central Motor Vehicles Rules have allowed passenger cars on tubeless tyres to drop the spare wheel if they carry a tyre repair kit and are fitted with a tyre pressure monitoring system. The Press Information Bureau’s summary of the notification describes the kit: sealant poured into the tyre with air seals the puncture in the tread. A kit cannot help with a cut sidewall, a large gash or a bent wheel, so if your car has one, know where the nearest tyre shop is before a long trip. Our tyre sealant guide explains how the kits work and their limits, and the tubeless puncture kit guide covers the string plug kits many owners add.

What pressure to keep the spare at

Full-size spare: use the pressure on your car’s door placard or in the handbook. Apollo Tyres suggests keeping the spare about 5 psi (0.3 kg/cm²) above the recommended figure, since it may sit unchecked for a while, and correcting it once the spare is fitted. Our pressure lookup has the placard figures for common Indian cars.

Space-saver: use the figure printed on its sidewall or in the handbook, typically 60 psi. That is about twice a normal car tyre’s pressure, so make sure your gauge reads that high and your pump can reach it.

How often: NHTSA’s advice is to check all tyres, including the spare, at least once a month, when the tyres are cold. Michelin’s minimum for the spare is once a year. Checking it with the others every month is the habit that pays off on the day you need it.

How far and how fast on a space-saver

The speed limit is the clear rule: 80 km/h in Kia’s handbook, or whatever figure your own handbook and the spare’s sidewall give. Distance is less clear. Kia’s manual gives no fixed number of kilometres; it says the spare should be replaced with a proper tyre and wheel at the first opportunity and warns that continuous use can lead to tyre failure. Take that literally: drive to a tyre shop, not to your destination three hundred kilometres away.

While the space-saver is on, drive as if the car is carrying a warning light. It is a narrow tyre with a short tread life, sitting lower than the others, so brake early, corner gently and keep well clear of potholes.

Spares age even when they are never used

A spare that has never touched the road still ages. NHTSA points out that spare tyres are prone to ageing because they are rarely replaced, and recommends that a full-size spare should not be used as a replacement for a worn tyre except in an emergency. Michelin’s rule of replacing tyres ten years after the date of manufacture applies to spares too.

To find your spare’s age, read the last four digits of the DOT code on its sidewall: the first two are the week, the last two the year. A spare marked 1216 was made in the twelfth week of 2016. Our tyre age check turns the code into an age for you.

Changing to the spare safely

Apollo Tyres’ step-by-step guide gives the order that keeps you safe:

1. Slow down, switch on the hazard lights and pull off well away from traffic, on flat, firm ground.
2. Switch off the engine, pull the parking brake, and wedge a wheel on the opposite side if you are on a slope.
3. Take out the spare and the tools. Find the jack point under the sill, set the jack and lift only until it takes the weight.
4. Loosen the wheel nuts slightly while the tyre is still on the ground.
5. Raise the car, remove the nuts and the flat wheel, and fit the spare.
6. Run the nuts on by hand, lower the car, then tighten them fully.
7. Check the spare’s pressure before you drive off.

Have the wheel nuts checked for tightness at the tyre shop, and get the punctured tyre repaired or replaced so you are not left without a spare.

If your car has no spare at all

If your car has only a repair kit, three habits help. Keep the compressor’s plug and hose in the boot with the bottle, check the sealant has not passed its shelf life, and learn where the tyre shops are on routes you use often. If you regularly drive on rough rural roads, where sidewall cuts are more likely, ask your dealer whether a spare wheel and jack can be fitted as an accessory.