How to put a classic car away for the winter

A car that sits still for five months is not being looked after. It is being left alone, which is a different thing. Most of the damage a stored car takes happens quietly, in the first few weeks, and almost all of it is avoidable in an afternoon.

This is what we tell people who keep collector cars with us, whether they store here or in their own garage.

Storage starts with a wash, and it is not vanity

Bird lime, tree sap and road salt all keep working after the car stops. Salt in particular holds moisture against metal for as long as it is there. Wash the car, get the underside and the wheel arches, dry it properly, and then wax it. The wax is a sacrificial layer between the paint and five months of still, slightly damp air.

Clean the interior in the same pass. Crumbs are what turns a parked car into somewhere a mouse wants to live.

Fuel: full tank, stabilizer, and run it through

A full tank leaves less room for the air that puts condensation in your fuel. Add a stabilizer at the dose on the bottle, then run the engine for ten or fifteen minutes so the treated fuel actually reaches the lines, the pump and the injectors or carburetor. Stabilizer sitting in the tank while untreated fuel sits everywhere else is the most common version of this job done badly.

Change the oil before, not after

Used oil carries acids and combustion by-products. Leaving it in the sump for the winter means leaving those against bearings and seals for months. Change it before the car goes away, and run the engine afterwards so the fresh oil is everywhere it should be.

Tires, and the flat spot question

Inflate to the pressure on the placard, or a few psi above it, because tires lose pressure slowly in the cold. Modern radials on a properly inflated tire will usually take a normal winter without a permanent flat spot; older bias-ply tires and very heavy cars are the ones that suffer. If you are storing for longer than a season, or the car is valuable enough that you would rather not find out, put it on jack stands with the suspension unloaded.

Battery: tender, not trickle

Use a modern battery tender that monitors and stops, rather than an old trickle charger that pushes current regardless. A tender keeps the battery at float and does not cook it. If there is no power where the car is parked, take the battery out and keep it somewhere dry and cool. A battery left flat over a winter is usually a battery you are replacing.

Parking brake off

Leave the parking brake off and chock the wheels instead. Brake pads left clamped against a disc for months can bond to it, particularly in damp air, and freeing them is a job you did not plan for.

Cover it with something that breathes

A soft, breathable indoor cover keeps dust off and lets moisture leave. A plastic tarp does the opposite: it traps humidity against the paint and turns the car into its own greenhouse. If you are covering a car in a heated indoor space, a light cotton or flannel-lined cover is enough.

Mice

They want warmth, insulation and quiet, and a stored car is all three. Do not leave food, do not leave paper, and block the obvious ways in. Steel wool in the exhaust tip works if, and only if, you attach a label to the steering wheel reminding yourself it is there.

What the building itself has to do

Everything above assumes the car is somewhere dry, level and a reasonable temperature. A hard floor matters more than people expect: a car parked on dirt or unsealed concrete sits in the moisture coming up through it, all winter, no matter what you did to the paint.

A heated indoor bay stops the freeze and thaw cycle that is hardest on seals, rubber and fluids. Behind a gate, on your own access code, it also means nobody is looking at your car who has no reason to.

Before you drive it again

Pull the cover, check the tire pressures, look underneath for anything that has taken up residence, and remember what you put in the exhaust. Start it and let it come up to temperature before you ask anything of it. Brakes will feel odd for the first few stops as surface rust comes off the discs; that is normal and it clears.