How to Prepare Your Car for Winter Storage — A 12-Step Checklist

Preparing a car for winter storage comes down to twelve things: wash and seal the paint, change the oil, fill and stabilise the fuel, set the tire pressures, keep the battery on a maintainer, leave the parking brake off, block rodent entry points, and cover the car with something breathable. Do all of it before the car sits, not after.

What are the 12 steps to prepare a car for winter storage?

The full sequence takes an afternoon and roughly $150 to $300 in consumables if you do it yourself. Work in this order, because a few steps depend on the ones before them. The single most common mistake is storing a car dirty and full of used oil, which does more damage over five months than the cold ever will.

1. Wash the car properly, including the underside. Ontario road brine is largely calcium and magnesium chloride, and both are hygroscopic: they pull moisture out of the air and keep corroding steel long after the car is dry to the touch. Pressure-rinse the wheel wells, subframe, rocker pinch welds and exhaust hangers, not just the paint you can see.
2. Dry it completely, then wax or seal the paint. Water sits in mirror housings, door jambs, tail light gaskets and the fuel filler recess. Blow those out with compressed air or a leaf blower. A coat of wax or a synthetic sealant gives the paint a sacrificial barrier for the months it will spend untouched. Treat any exposed chrome or bare metal separately, since chrome pitting starts at pinholes in the plating and spreads underneath.
3. Strip the interior of anything organic. Wrappers, coffee cups, the half-bag of dog treats under the seat. Damp floor mats should come out and dry separately. Mice are looking for food and nesting material, and a clean cabin is far less interesting to them than a dirty one.
4. Change the oil and the filter. This is a before-storage job, not a spring job. See the section below for why.
5. Check the coolant and top up the rest. A 50/50 ethylene glycol mix protects to roughly −37 °C, which is more than Ontario needs, but a weak or old mix will not. Brake fluid is hygroscopic as well: DOT 3 and DOT 4 absorb moisture from the atmosphere, and fluid that is more than two or three years old is worth flushing before it sits.
6. Fill the tank to about 95% and add a fuel stabiliser. Less air space above the fuel means less condensation on the tank walls and less oxygen contact. Add the stabiliser first, then run the engine for 10 to 15 minutes so treated fuel reaches the fuel rail, injectors, or carburettor bowls. Untreated pump gasoline starts oxidising within about 30 days.
7. Set the tire pressures. Inflate to the placard figure or a few psi above it. Pressure falls roughly 1 psi for every 5.5 °C drop in temperature, so a tire set on a mild October afternoon will read noticeably lower by January even in a heated space.
8. Sort out the battery. Either remove it or connect an intelligent maintainer. Details below.
9. Leave the parking brake off and chock the wheels. Pads left clamped against a rotor for months can bond to the surface through surface corrosion, and on drum brakes the shoes can seize to the drum. Use wheel chocks and, on a manual, leave it in gear.
10. Block rodent entry points. Steel wool in the exhaust tip and over the air intake, removed and noted on a checklist so you do not start the engine with it still in place. Skip the mothballs. Naphthalene vapour will get into upholstery and headliner and the smell is very difficult to remove.
11. Cover the car with a breathable cover. A plastic tarp traps moisture against the paint and abrades it every time air moves underneath. A breathable cotton or multi-layer cover lets vapour escape. Slip a strip of plastic film under the wiper blades so the rubber does not bond to the glass. In a secure, climate-controlled space you can leave the windows down a centimetre to keep the cabin from going musty; in an unattended home garage, do not.
12. Record the odometer, photograph the car, and speak to your broker. Date-stamped photos of each panel and the odometer give you a clear before-and-after record. Storage also changes how a vehicle is insured, and that conversation belongs with your broker, not a blog.

Should I change the oil before or after winter storage?

Before. Used engine oil carries acidic combustion by-products, including sulphuric and nitric acid compounds formed from blow-by gases, along with fuel dilution and suspended water. Leaving that mixture sitting against bearing shells, camshaft lobes and cylinder walls for five months allows it to etch those surfaces.

Fresh oil has a full additive package, including corrosion inhibitors and acid-neutralising detergents, and none of the contamination. Change the filter at the same time, since a used filter holds a reservoir of dirty oil regardless of what is in the sump.

Run the engine to operating temperature after the change so the new oil is distributed through the galleries and the last of the old oil is displaced, then shut it down and leave it. You do not need a second change in spring unless the car has sat for well over a year.

Should I remove my car battery for winter storage?

Not if you can leave it connected to an intelligent maintainer instead. A modern vehicle draws a parasitic current of roughly 20 to 50 milliamps even when parked, for keep-alive memory, alarm circuits and telematics, and that draw alone will flatten a healthy battery over a winter. Pulling the battery stops the drain but does not stop self-discharge, which runs at about 3% to 5% a month for a flooded lead-acid battery.

The real damage is sulphation. As a lead-acid battery sits discharged, lead sulphate crystals harden on the plates and permanently reduce capacity. A discharged battery is also far more vulnerable to freezing: a fully charged one resists freezing well below −40 °C, while a deeply discharged one can freeze near −7 °C, which cracks cases and buckles plates.

An intelligent maintainer, as opposed to a plain trickle charger, monitors state of charge and only charges when needed. That matters, because a constant-current trickle charger left connected for five months will overcharge and boil off electrolyte. If the car has no power available where it is parked, remove the battery, store it somewhere above freezing on a shelf rather than a concrete floor, and charge it monthly.

Will my tires flat-spot over the winter?

Probably, to some degree, and on most modern cars it resolves itself. A tire sitting under load with the carcass at rest takes a temporary set in the contact patch. On a current radial with nylon-reinforced belts, that set usually works out within the first few kilometres once the tire warms to operating temperature.

Older tires are a different case. Bias-ply construction and older radial compounds can take a permanent set if the car sits for months at low pressure in a cold space, and that shows up as a vibration that never goes away. Owners of period-correct cars on original-spec rubber should either run pressures at the upper end of the range or take the load off entirely. This is one of the reasons classic car storage tends to involve more hands-on management than storing a late-model daily driver.

Temperature stability helps here as well. A tire that is repeatedly cycled from −15 °C to above freezing loses and regains pressure with every swing, and it is the low-pressure part of that cycle that does the damage.

Is a home garage good enough, or should I use a storage facility?

An attached, heated garage with a power outlet is fine for most cars. An unheated detached garage is where problems start, because it swings with the outside temperature. When a cold metal body sits at −10 °C and warm humid air moves in during a thaw, moisture condenses on every surface, including the ones inside door skins and under carpet, where it will not dry.

Humidity control is the part homeowners rarely replicate. Steel corrodes slowly below about 50% relative humidity and much faster above roughly 60%, which is why regulated humidity matters as much as regulated temperature. That is the practical argument for indoor car storage over a driveway, a car port, or an unconditioned garage.

Security is the second argument. Toronto recorded 7,305 auto thefts in 2025, a 32.2% year-over-year decline according to Toronto Police Service data, and Ontario as a whole fell from 24,877 in 2024 to 19,319 in 2025. The trend is not uniform, though: in the first half of 2026, Équité Association; reported Toronto up 8.8% while the provincial total fell 8.4%. A car parked in a residential driveway from November to April is a stationary, unmonitored target for five months.

What should I sort out with insurance and paperwork before storing?

Talk to your broker before the car goes in, not after. Insurers generally treat a vehicle that is off the road and stored differently from one in daily use, and the arrangements available vary between companies and by what you are storing. Some facilities also ask to see proof of current coverage before accepting a vehicle.

Do not cancel coverage outright. A stored car can still be damaged or stolen, and a lapse creates its own problems when you go to insure it again. What is or is not covered while a car is in storage depends entirely on your policy and your insurer, so get the answer in writing from the person who wrote it.

Keep the ownership, a spare key and your service records somewhere separate from the vehicle. If you are storing for longer than a single season, the same logic applies to long-term vehicle storage, where documentation gaps tend to surface at resale.

How MyAutoStorage handles winter preparation

MyAutoStorage is a boutique facility in Etobicoke run by two brothers, Mike and Rob, both long-time collectors. Every vehicle stored for winter car storage in Toronto gets the same specification with no tiers: a climate-controlled environment with regulated temperature and humidity, an intelligent battery tender connection, tire pressure monitoring, fuel stabilisation, regular visual inspections, a protective cover, electronic gated access with logged entry, and 24/7 CCTV. Winter prep, detailing, GTA pickup and delivery and a spring readiness package are available on request. Standard vehicles start from $250 per month, and the seasonal winter package starts at $1,250 for 5 months; current storage pricing is published in full. Seasonal spots are limited and usually fill by late September, so get in touch or call +1 (416) 571-7955 before then.

5. FAQ

Should I start my car every few weeks during winter storage?

No. A short idle warms the engine enough to draw moisture and fuel into the crankcase but not long enough to evaporate them back out, so you end up with more contamination in the oil than if you had left it alone. It also partially discharges the battery each time. If the car is on a maintainer with fresh oil and stabilised fuel, leave it until spring.

Is it worth putting the car on jack stands for the winter?

For most cars, no. Five months on properly inflated modern radials will not cause lasting harm, and unloading the suspension for long periods puts shocks and half-shafts at full droop, which is not ideal either. Jack stands are worth it for cars on old or bias-ply tires, or for storage running well beyond a single season, where permanent flat-spotting becomes a real risk.

What should I do before driving the car again in spring?

Remove any steel wool from the exhaust and intake, check underneath for nesting material, reconnect the battery, and set the tire pressures at ambient temperature. Check the coolant and brake fluid levels, look for fluid on the floor, and inspect the wiper blades and rubber seals. Then drive gently for the first 20 to 30 kilometres so the brakes clean up any surface rust on the rotors.

Do I need to take the car off the road or remove the plate?

Requirements around plates, registration and insurance while a vehicle is off the road vary by situation, and both ServiceOntario and your insurance broker are the right sources. In general terms, keeping the registration valid is simpler than reinstating it, and most owners keep the plate on the car. Confirm your specific case with your broker before you make any change.

When should I book a winter storage spot in the GTA?

Aim for late summer or early September. Seasonal capacity at climate-controlled facilities in the Toronto area is finite, and boutique facilities have deliberately small vehicle counts. At MyAutoStorage, seasonal spots typically fill by late September, which means the owners booking in October are usually the ones who left it too long.