Winter Car Care: How to Get Your Car Ready for the Cold

The first proper frost every year, my phone doesn't stop.

Same call, over and over. Turned the key, got a click and a groan, nothing. And nearly every one of them is a battery that was already tired in October and nobody checked it.

That's the thing about winter car problems. They're almost never surprises. They're things that were quietly going wrong for months, and the cold just finished them off.

So here's the whole lot. What to check, when to do it, and the bits people get wrong.

If you do nothing else, do these five. They cover the vast majority of what I get called out to between November and February.

1. Get the battery tested. If it's over five years old, or it cranks slowly on a cold morning, it's living on borrowed time.
2. Check your tyre tread and pressures. Aim for 3mm, not the 1.6mm legal minimum. Cold air drops your pressures every week.
3. Test your antifreeze concentration. A tester costs about a fiver. It should protect to at least minus 20.
4. Walk round every light. Then clean them, because road salt and spray cut light output dramatically.
5. Fill the washer bottle with proper winter screenwash. Not diluted. Not washing-up liquid.

Twenty minutes, most of it in your own driveway. Now the detail.

At around freezing, a car battery loses roughly 40 per cent of its capacity. At the same time, the engine needs considerably more power to turn over, because the oil is thicker and everything is stiffer.

Less power available, more power needed. That's the whole problem in one sentence.

The warning signs:

• ▸The engine cranks slower than it used to, especially first thing
• ▸Headlights dim noticeably when you start it
• ▸The battery warning light comes on, even briefly
• ▸Electrics behave oddly, dash flickers, radio resets
• ▸It's five years old or more

What to do:

Get it tested. A proper load test tells you the state of the battery under load, which is entirely different from whether the car started this morning. I do this free, and it takes minutes.

While you're there, look at the terminals. That white or blue crusty stuff is corrosion and it stops the battery charging properly. Clean it off. And check the battery is actually clamped down, because one that rattles about will fail early.

The uncomfortable truth is that most batteries give very little warning. They work, and then one morning they don't, and it's always the coldest morning and always when you're late. Testing it in October costs nothing and saves the whole performance.

More detail in the seven signs your battery is dying, and worth knowing: a lot of the batteries that die in November were actually killed by the summer heat.

Your tyres are the only part of the car touching the road, and in winter that matters more than at any other time of year.

Tread depth. The legal minimum is 1.6mm. For winter, aim for 3mm or more. Below 3mm your wet braking distance stretches out significantly, and on ice it's worse again. If yours are close to the limit now, replace them before winter rather than after, because you'll need them either way.

The 20p test is the quick check. Push a 20p into the main tread grooves. If the outer band on the coin is visible, the tread is too low.

Pressures. Cold air contracts, so pressures drop as the temperature falls. Check them weekly through winter, and check them when they're cold, not after a long drive. Correct pressures give you better grip and better fuel economy.

Winter tyres. Worth considering if you live somewhere rural or hilly. The rubber compound stays soft below about 7 degrees where normal tyres go hard and lose grip, and the difference on ice is not subtle. For most Black Country driving, decent all-season or summer tyres with plenty of tread are fine.

Antifreeze does three jobs, and only one of them is in the name. It stops the coolant freezing, it stops the cooling system corroding from the inside, and it lubricates the water pump.

Weak or old coolant fails at all three.

What to check. Buy an antifreeze tester, they're about £5 from any motor factor. Your concentration should protect to at least minus 20 for a UK winter.

Warning signs something's wrong:

• ▸A sweet smell around the engine bay
• ▸White smoke from the exhaust that doesn't clear
• ▸The temperature gauge sitting higher or lower than normal
• ▸Coolant level dropping with no obvious puddle

One thing not to do. Don't mix different coolant types. They can react with each other and turn to a jelly that blocks the system completely. If you don't know what's in there, drain it and refill with fresh.

Frozen coolant cracks engine blocks. It's a rare failure but it's a terminal one, and a £5 tester prevents it.

Winter means driving in the dark far more, in worse weather, with more spray.

Check every one: headlights on dipped and full beam, sidelights, indicators front and rear, brake lights including the high level one, reversing lights, number plate light, and both fog lights.

Do it against a garage door or shop window if you're on your own, and get someone to press the brake pedal while you look.

Then clean them. Road salt and spray build up a film on the lenses that cuts light output by more than half. Give them a wipe every time you fill up. It's the cheapest visibility improvement there is.

A quick note on fog lights: they're for fog and heavy snow only. Using them in ordinary rain or darkness dazzles the people behind you, and it's an offence.

Visibility is the thing that catches people out most in winter.

Screenwash. Use proper winter screenwash rated to at least minus 15, and don't over-dilute it to make it go further. A frozen washer system on a salty motorway is genuinely dangerous, because you can't clear the screen and you can't stop safely either. Keep a spare bottle in the boot. You'll use far more than you expect.

Never use washing-up liquid. It damages the pump seals and it freezes.

Wipers. Replace them if they streak, judder or squeak. Always clear the ice off the blade rubber before you use them, because dragging a frozen blade across a frozen screen tears the rubber and ruins it in one go.

If a hard frost is forecast, lift the wipers off the screen overnight so they don't freeze to the glass.

Demisting. Keep the inside of the glass clean, because dirt and film make misting far worse. Use the air conditioning if you have it, even in winter, because it dries the air and clears the screen much faster than heat alone.

Never use boiling water. The thermal shock can crack the windscreen, and it's an expensive way to save two minutes. This is the single most common winter mistake I see.

Use a proper de-icer and a scraper. Start the engine and let the heater work on the inside while you clear the outside.

Clear all the glass, all the mirrors, all the lights, and the roof. Snow left on the roof slides down onto your windscreen the first time you brake hard, or onto the car behind you. Driving off with a small cleared patch in front of the steering wheel is illegal as well as daft.

Give yourself the extra five minutes. Everyone knows this and nobody does it.

Cold oil is thick oil, and thick oil is harder to pump round an engine at the moment it most needs lubricating, which is the first few seconds after a cold start.

Check your handbook for the permitted grades. If a thinner winter grade is allowed, such as 5W-30 rather than 10W-40, it will flow better on cold mornings and reduce wear. The first number is the cold rating, so lower is better in winter.

Check the level monthly, and more often if the car uses oil. Engines tend to use a bit more in cold weather.

Full detail in when to change your engine oil.

Belts and hoses. Rubber goes hard and brittle in the cold, so weak spots that survived the summer often let go in January. Look for cracks, splits, bulges and anything weeping at a joint.

Brake fluid. It absorbs moisture from the air over time, and water in the brake system is bad news in freezing weather. It should be changed every two to three years regardless. If you can't remember when yours was done, it's due.

Screenwash and coolant levels. Both while the bonnet is up.

Door locks freeze. A squirt of de-icer in the keyhole clears it, and WD-40 beforehand stops it happening.

Door seals freeze to the bodywork. Rub them with a little talcum powder or silicone and they won't stick. Never yank a frozen door, because you'll tear the seal and then it leaks all year.

Fuel flaps freeze too, usually at the least convenient moment.

All winter: ice scraper and de-icer, jump leads or a jump pack, torch, phone charger, hi-viz vest, warning triangle, first aid kit.

For longer journeys: a blanket or a warm coat, water, something to eat, and if you're going anywhere rural or hilly, a small shovel and something for grip like an old bit of carpet or a bag of cat litter.

Also worth doing: keep the tank above a quarter. Condensation in a near-empty tank can freeze in the fuel lines, and a decent amount of fuel means you can run the engine for heat if you're stuck.

Once the car's ready, the other half is how you drive.

• ▸Allow far more time than you think
• ▸Stopping distances can be up to ten times longer on ice
• ▸Everything gentle: acceleration, braking, steering
• ▸Pull away in second gear on snow to reduce wheelspin
• ▸Higher gear, lower revs, more control
• ▸If you start to slide, come off the accelerator and steer where you want to go. Don't stamp on the brake

The checks that go out of date fastest are the ones worth repeating mid-season.

Re-test the antifreeze, because it degrades. Check the tyre pressures again, because they'll have dropped. Get the battery re-tested if it's been standing a lot or doing short journeys, because short cold trips never fully recharge it. And top the screenwash up, because you'll have got through more than you think.

Fifteen minutes in January catches the things that survived December on borrowed time. There's more on this in the five car problems every UK driver hits in January.

October or early November. Before the first hard frost, not after it.

That's the whole point. Everything on this page is cheap and easy in October, and everything on this page is expensive and urgent in January when you're stood on a driveway at seven in the morning in the dark.

If you drive an electric car, the cold hits range hard and there are different things to do. Those are covered in electric car battery care in winter.

If you'd rather someone just did it, I do a winter check for £95, and it's free if you book a basic or full service at the same time.

Battery health and charge under load, antifreeze concentration, every light, wiper condition, tyre tread and pressures, brake condition, heater and demister operation. I top up the screenwash while I'm there and tell you straight if anything needs attention.

It pairs well with a full service if one's due anyway, and if the brakes or the battery are the concern then brake repairs or a battery replacement can be done on the same visit.

We come to you across the Black Country, from Dudley and Stourbridge to Halesowen and Kingswinford. You don't have to go anywhere.

Almost nothing on this page is exciting, and almost none of it costs much.

But every winter I pull up next to someone who's late for work, stood in the cold next to a car that won't start, and in nine cases out of ten it's something we could have found in October for the price of a takeaway.

Book it before the clocks change. That's genuinely all the advice there is.