Before a long journey, and before a long stand

In everyday use a car hides its weaknesses. A weak battery does not show while it is charged daily. A tyre with little tread copes as long as you are not crossing a pass in heavy rain. A brake pad at the end of its life is enough for town. Only the exception brings those things forward, and then all at once.

Preparing for both is therefore the same act: looking once at what everyday use never looks at. For the long journey, because everything is loaded at the same time. For the long stand, because processes run there that movement otherwise prevents.

The date for the check is a week before departure, and the reason is mundane: whatever you find needs a workshop slot and a part, and neither exists the evening before. A week's notice turns a finding into a repair; an evening's notice turns it into a journey with a known problem.

Tyre pressure is measured cold and set for the load you will actually carry — the label on the car usually carries a second, higher figure for a fully occupied vehicle. A fully loaded car running the pressure meant for an empty town trip has an overheated sidewall, a longer stopping distance and measurably higher consumption.

One simple rule saves a lot of trouble: anything that would otherwise be “next time” becomes “now” if next time falls on a motorway in another country. A service that would come due during the trip is done beforehand. So is an oil change that is close.

With brakes this applies especially. A pad near its wear limit is enough for everyday use and not for a loaded descent of a pass, where the same brake does work it otherwise never does. The same goes for brake fluid: over the years it draws water and loses boiling point, and on that descent the boiling point becomes the relevant figure.

And the tyres. A tyre at the end of its tread is unremarkable on a dry road and, in heavy rain at speed, the component that gives up first. If you need new tyres this season anyway, buy them before the trip rather than after — the same expense, a different benefit.

The permitted gross weight is in the registration documents, as is the kerb weight; the difference is the payload, and it includes the people. A fully occupied car with luggage reaches that limit faster than most assume. Roof load has its own separate limit, in the handbook — and it includes the rack itself.

Where the weight sits matters as much as how much of it there is. Heavy items belong low and as close to the rear axle as possible, not behind it and not high up; weight far back and high makes the car sluggish in an avoidance manoeuvre and then suddenly unwilling. Nothing lies loose behind the heads of the people in the back — a suitcase that comes forward under emergency braking is no longer a suitcase.

A roof box changes three things at once: consumption, crosswind behaviour and the height of the car. Write the new height on a note you can see from the driver's seat — car parks and underpasses do not allow for what is on top. And a towbar has its own nose weight, which acts on the rear axle in addition and has to be counted in.

At every fuel stop, one lap around the car: look at the tyres rather than walking past them; look underneath for fresh drips that were not there before; and check the load, especially on the roof, because a rack settles. It takes a minute and finds the things that build up over hours.

Check the oil level at least once on a long trip, and more often on an engine known to use oil. The moment matters: a cold engine on level ground, or the manufacturer's procedure where the car measures the level electronically. A reading taken after twenty minutes of motorway is not a reading.

On a long descent you do not brake continuously; you change down — engine braking works for hours, a friction brake does not. If you smell hot brakes or the pedal goes long, only one thing helps: stop where it is safe and wait. Cooling means air and time, and expressly not water; cold water on a glowing disc warps it.

A car standing still is not a car without wear but a car with different wear. The battery discharges through the quiescent draw every modern vehicle takes, and a deeply discharged lead battery sulphates — it loses capacity permanently, not merely until the next charge.

The tyres develop a flat spot at the contact patch, which drives out again after a short stand and does not after a long one. The brake discs rust, and the rust bonds disc to pad; a handbrake left on for months can seize a drum or a caliper. Fuel ages — petrol with an ethanol fraction faster than diesel — and condensation forms in a half-empty tank.

And two things almost nobody thinks of. The air-conditioning loses refrigerant through its seals when the compressor never runs and its shaft seal dries out. And a warm engine bay is the most popular place in the neighbourhood for rodents in winter; the consequences show on cable insulation and sound deadening, not on the bodywork.

Clean and dry, and that goes above all for the underside if the car has seen road salt — salt keeps working while the car stands. Fill the tank as far as possible, so little air is left for water to condense in. Then the car is best kept dry and ventilated; a breathable cover helps, a plastic sheet does damage, because it traps moisture.

The battery is the single most important decision. A trickle charger is the most convenient solution and needs a power point. Disconnecting is the alternative, but it has side effects worth knowing in advance: radio code, window and roof positions, learned values and, depending on the car, settings a workshop has to reset. Which ones those are is in the handbook.

For a long stand in a damp place the handbrake is better left off; secure the car with chocks and, on a manual, with a gear engaged. Raise the tyre pressures to limit the flat spot. And for genuinely long periods, putting the car on stands is the clean solution, because it unloads tyres and springs at the same time.

Do not simply drive off. First the tyre pressures and a look at the sidewalls, then the fluid levels, then a look into the engine bay and under the car — for nests, chewed insulation and traces of fluid on the ground. Test the battery under load; a resting voltage says little about an aged battery.

The first braking feels rough and rumbles, because a film of rust lies on the discs. It wears off — on an empty road, with several moderate applications in succession rather than one hard one. If the rumble stays afterwards, the rust sits deeper, and that is a workshop finding and not a bedding-in process.

And the first drive is not a lap of the block. It is long enough for the engine, gearbox and exhaust to get properly hot — only then does the condensation evaporate out of the oil and the exhaust, only then does the battery charge for more than a few minutes, and only then can a particulate filter finish an interrupted regeneration.