A five-minute tyre check before you load the car helps prevent tyre trouble on the road. A long, fully loaded drive is exactly when a marginal tyre lets go, so it pays to look at tread, pressures and condition before you set off, while you can still do something about it. Here's the checklist worth running before any weekend away.
Why check before a trip
Road trips combine the things that stress tyres: high mileage, a heavy load, sustained speed and often hot or cold extremes. A tyre that copes fine with short local trips can struggle under those conditions. Catching a low pressure, a worn tyre or a hidden nail at home is a two-minute job; discovering it on the hard shoulder is a ruined day.
The five-minute checklist
The UK tyre safety charity TyreSafe boils a good check down to three things, the ACT check: Air pressure, Condition and Tread depth.
- Tread: do the 20p test on all four tyres, including the inner edges. The legal minimum is 1.6mm across the central three quarters of the tread.
- Pressure: set them cold to the recommended figure.
- Condition: look all round for cracks, bulges and embedded nails.
- Age: a quick glance for perished or very old tyres.
Don't forget the load
A full car of people and luggage weighs a lot more than your daily commute, and the tyres need more pressure to support it. Use the higher "laden" figure on your door placard for a loaded trip, or the tyres will be effectively under-inflated, which raises heat and blowout risk on a long, fast drive.
Check the spare or kit
The one tyre everyone forgets is the spare, which is often flat or perished when you finally need it. Check its pressure and condition, or make sure your repair kit is in date. A working get-you-going option is worth having before a trip away from home.
The day before and the morning of
Split the check across two days: anything that needs a new tyre must be found the day before, because nothing gets fitted at six in the morning on departure day. The morning check is then a quick confirmation rather than a discovery.
| When | What to do | Why then |
|---|---|---|
| Two or three days before | 20p test on all four tyres, inner and outer edges. Walk round looking for cracks, bulges, nails and screws. Check the spare, or the repair kit's expiry date. | Leaves time to have a tyre replaced at home if one fails the check. |
| The evening before | Set pressures cold to the laden figure. Find the locking wheel nut key and put it in the glovebox. | Tyres are cold after a day parked, so the reading is accurate. |
| Departure morning | Glance at each tyre for one that sits lower than the others. Look under the car for a screw picked up on the last drive. | A tyre that has dropped overnight is telling you it has a slow leak. |
| At the first fuel stop | Hold a hand near each tyre for one that is far hotter than the rest, and look for a new lump on a sidewall. | An under-inflated or damaged tyre runs hot before it fails. |
If one tyre is noticeably lower than the others on departure morning, do not top it up and hope. A tyre that has dropped several PSI overnight has a slow puncture, and a long, fast, loaded drive is the worst possible test for it.
Roof boxes, bikes and the load index
Every tyre has a load index on its sidewall, and a full car with a roof box and a bike rack gets closer to that limit than most people expect. The number after the tyre size (the 91 in 205/55 R16 91V, for example) is a code for the maximum weight each tyre can carry at its correct pressure.
Your car's maximum weight is on the VIN plate, usually in the door shut or under the bonnet, and the handbook gives the maximum roof load. Add up passengers, luggage, roof box, rack and bikes and a small hatchback reaches its limit quickly. Our guide to load and speed ratings explains how to read the code.
Two practical rules follow. First, the laden pressure on the placard assumes the car is loaded to its design limit, so use it. Second, keep heavy items low and between the axles rather than in the roof box, which raises the centre of gravity and loads the rear tyres unevenly.
A car with the rear sitting visibly lower than the front is overloaded at the back, whatever the paperwork says. If you are towing, the caravan or trailer tyres need the same check and often more attention, because they sit unused for months.
Tyres on a long motorway run
Sustained motorway speed builds heat in a tyre, and heat is what turns a small weakness into a failure. The Highway Code recommends a break of at least 15 minutes after every two hours of driving (rule 91), and those breaks are also the moment to walk round the car.
At each stop, look for a tyre that appears lower than its partner on the same axle, and glance at the sidewalls for a new lump after a pothole or a hard kerb strike on the way in.
Do not let air out of hot tyres to "correct" a reading. Warm tyres read a few PSI higher than cold, and bleeding them to the placard figure leaves them under-inflated once they cool.
Watch for changes in the car rather than the tyres. A new vibration through the wheel, a pull to one side, or a rhythmic noise that rises with speed are all worth a stop at the next services rather than pressing on.
If a tyre fails on the way
A tyre problem on a motorway is a stop-and-get-safe situation, not a change-it-yourself one.
The Highway Code's breakdown rules (rules 274 to 278) are clear: get the car off the carriageway if you can, leave by the passenger side, get everyone behind the barrier and up the bank, and never attempt a repair on a hard shoulder or in an emergency refuge area.
- If you cannot leave a live lane, stay belted in with the hazard lights on and call 999.
- From a hard shoulder or refuge area, call National Highways on 0300 123 5000 or use an emergency telephone, and they will help you arrange recovery to a safe place.
- On an ordinary road, pull into a lay-by, side road or car park rather than stopping on a bend or a verge with no room to work.
Once the car is somewhere safe and off the road, a mobile fitter can come to it. Within our area, a mobile fitter can work at motorway services or in a car park if the operator agrees, or on a driveway, so a failed tyre does not always have to mean a tow to a garage and a lost day.
Read what to do in a blowout before you go, while it is calm.
Pre-trip fit at home
If your check turns up a worn or damaged tyre, we can replace it at your home before your trip if the diary allows, from our one base at Brent Cross, NW2. If you are further out, we tell you on the call whether we can take the job.
