Laying Up a Classic Car for Winter: An Oil and Lubrication Checklist

The best lay-up routine for a classic car starts with fresh oil, a thorough grease-up and protection against moisture, and ends with a careful wake-up in spring. Used engine oil holds acids and moisture that attack metal surfaces during a long sit, so changing it before storage is one of the most useful things you can do. This checklist covers the lubrication side; follow your workshop manual for anything specific to your car.

Why storage is hard on an engine

A car that sits for months does not stand still chemically. Moisture condenses inside the engine as temperatures change, combustion by-products in used oil turn corrosive, and oil drains away from surfaces such as cylinder walls and cam lobes. Rust can form on bores and bearing journals, and seals can dry out and shrink. The fix is to start storage with clean oil, and in many cases to use a dedicated preservation oil.

Step 1: change the engine oil and filter

Do this at the end of the season, not at the start of the next one. Warm the engine, drain it fully, fit a new filter and refill with fresh oil. Then run the engine to full temperature before the final shutdown, so the fresh oil, and the inhibitors in a preservation oil, reach every surface instead of sitting in the sump. Some owners go one step further and use a preservation oil for the lay-up period. For choosing a normal oil, see our classic car engine oil guide.

Step 2: consider a preservation oil

A preservation oil is a mineral oil with rust-inhibiting additives meant for engines that sit or run lightly. Millers Classic Preservation Oil 20W-50 is a mineral SAE 20W-50 preservation oil for classic engines and gearboxes, described as protecting petrol and diesel engines against rust and corrosion, with vapour-phase inhibitors that protect working surfaces and resistance to draining away during long storage. The oil may also be driven on gently; Millers quotes up to 2,000 quiet road miles, so an occasional proper drive during the lay-up is fine. It can be used in gearboxes that call for engine oil. In hypoid final drives it is only suitable for storage, not for service.

The product guidance is clear on one point: before the engine goes back into regular use, change to the engine oil that suits it. That is a good habit generally. Ask your engine builder or a marque specialist if you are unsure whether preservation oil is appropriate for your car.

Step 3: gearbox, differential and other oils

• Check the levels in the gearbox, overdrive and rear axle. If they are due for a change, do it before lay-up so that fresh oil, not old, sits in the housings.
• Look for weeps from seals and gaskets; fix them before they become puddles on the garage floor.
• If you use gear oil, match the specification to the housing. Our article on GL-4 vs GL-5 gear oil explains the difference.
• Check automatic transmission fluid level and condition. See ATF Type A vs Type F if you are not sure which fluid your transmission uses.

Step 4: grease and lubricate

Chassis points, king pins, ball joints, propshaft joints, wheel bearings where accessible, door hinges, bonnet and boot catches, handbrake linkage and throttle linkage all benefit from fresh lubrication. Pump grease into nipples until fresh grease appears, and wipe away the excess so it does not collect dirt. Choose a grease that matches the component: wheel bearings, chassis points and water-exposed parts can need different types. Browse our greases collection, and read the product information for the intended use of each.

Step 5: other fluids

• Brake fluid absorbs moisture over time. If it is due, change it before storage. Never mix DOT 5 (silicone) brake fluid with DOT 3, 4 or 5.1; if you are unsure what is in the system, ask a specialist.
• Coolant should have the right antifreeze strength for your winter, and the system should be free of leaks.
• Fuel: fill the tank to reduce condensation, and consider a stabiliser if the car will sit a long time. E5 and E10 petrol absorb moisture and can attack old rubber hoses and carburettor parts over a long lay-up, so ethanol-free fuel is the safer choice for storage where you can get it. Check what suits your fuel system.

Step 6: the rest of the car

• Wash and dry the car completely, including door shuts and sills, before it goes under a breathable cover.
• Disconnect the battery and keep it on a maintenance (float) charger.
• Raise tyre pressure a little, or put the car on stands so the weight is off the tyres.
• Leave the handbrake off if the shoes could stick; use wheel chocks.
• Keep the garage ventilated and dry. Moisture is the main enemy.

During storage

Resist the urge to start the car for a few minutes now and then. A short idle run produces water vapour and fuel dilution without ever warming the engine fully, which is worse than leaving it alone. If you want to exercise the car, take it out for a proper drive so it reaches full temperature, and only in suitable weather. If you cannot, leave it be.

Waking the car up in spring

1. Check for leaks and the condition of hoses, belts and tyres.
2. If you used preservation oil, change to the normal engine oil and filter before regular use.
3. Check all fluid levels, brake pedal feel and battery condition.
4. Turn the engine over without starting it, if your manual allows, to build oil pressure; then start it, watch the oil pressure and let it warm up gently.
5. Drive gently for the first miles and re-check for leaks afterwards.

Frequently asked questions

Should I change the oil before or after winter storage?

Before. Used oil contains acids and moisture that can harm the engine during a long sit.

Do I need preservation oil?

It is not essential for every car, but it adds a layer of protection for engines that sit for long periods. Ask your specialist if you are unsure.

Can I leave the car with a full tank?

A full tank reduces condensation, but check that your fuel suits long storage.

Is it fine to start the engine once a month?

It is better not to unless you can drive the car to full temperature.

Summary

Fresh oil, fresh grease and dry storage take little time compared with the cost of repairing corrosion. Use your manual as the final authority, and if your car has unusual requirements, ask a marque specialist. Browse our classic oils collection to prepare for the new season.