October and November bring the same conversation in the workshop: "It started fine all summer." Cold mornings are unforgiving. They surface a marginal battery, a tired alternator, a coolant pump that has been on borrowed time since August. The cars we see breaking down in November are almost never doing so for new reasons — they are doing so because the cold has stripped the slack out of an old fault.
Here are the eight pieces of pre-winter preparation we recommend to every client who books a seasonal check, in roughly the order we'd do them ourselves.
1. Battery health-check (not just a voltage reading)
A multimeter on the terminals will tell you the resting voltage. It will not tell you whether the battery still has the cold-cranking amps it had the day it was fitted. A proper load-test under simulated start conditions takes ten minutes and is the single most valuable thing you can do for a car going into winter. If the battery is more than four years old, the calculus changes: a £140 replacement now is materially cheaper than the £180 jump-start callout when it gives up at the school gates in January.
2. Coolant strength and condition
Engine coolant has two jobs in winter: heat transfer (keeping the engine warm enough to run efficiently) and freeze prevention (stopping the cylinder block cracking when the temperature drops below freezing point). Both depend on the antifreeze concentration. A refractometer test takes seconds, and we will quietly do it for free during any service in October or November. If the protection has dropped below -25°C, we recommend a coolant flush and refresh.
3. Tyre tread and rubber compound
UK law requires 1.6 mm of tread depth. Stopping distance on a wet road at 1.6 mm is roughly twice the distance at 3 mm. The honest workshop number to aim for, going into winter, is 3 mm or above on all four corners. Older tyres — five years and beyond on the date code — also harden, regardless of remaining tread, and lose grip in cold conditions. The four-digit code on the sidewall is the manufacture week and year; if it begins with 24 or earlier and ends in 18 or 19, the rubber is past its useful winter life.
4. Wiper blades and washer-fluid concentrate
Two cheap items. New blades restore visibility in the kind of weather where visibility matters most. Concentrated washer-fluid stops the jets icing up and stops the lines themselves freezing — plain water in a washer bottle is a bad first morning of December waiting to happen.
5. Brake-pad and disc inspection
Cold mornings expose marginal brakes the same way they expose marginal batteries. A pad with 2 mm left in October will be screeching by November, and the squeal often happens at exactly the moment a small child runs into the road. A workshop visit costs nothing if everything is healthy, and is a small, contained job if the pads are due.
6. Lighting check, both bulbs and aim
Walk around the car with the lights on, including the indicators, fog lights and reverse light. Replace any failed bulb. While you are there, check the headlight aim is sensible — a heavy load in the boot pitches the beam up and dazzles oncoming drivers, so unload it before you set the headlight-level switch on a wet night.
7. Heating and demist function
If the heater is slow to warm in October, it will be useless in January. Slow heat usually means a sticking thermostat or a clogged matrix; either is straightforward to address before the weather makes it urgent. Demist relies on the air-conditioning compressor running to dry the cabin air, so a non-functional air-con system in winter affects safety as much as a non-functional one in summer.
8. An honest fluid top-up
Engine oil, brake fluid, washer fluid, and (if applicable) the manual gearbox or transfer-case oil. None of these top-ups cost much; all of them quietly extend life by months. If the oil on the dipstick looks like coffee, that is a service overdue, not a top-up situation.
And three things we'd politely skip
- "Winter additives" for the fuel tank. Modern fuel is already winterised at the refinery for the climate it's sold in.
- Aftermarket undertray sprays. Beyond a clean and a routine cavity-wax inspection, most aftermarket coatings do more for the marketing than the metal.
- "Winter wheel" packages on a daily-driven car that doesn't leave the south-east. Year-round all-season tyres on a sensible compound are a better answer for most owners.
If you would like the eight-point check above done in one visit, we offer it as a fixed-price seasonal-check service from October through January. It takes about an hour and includes the report in writing.