The importance of the right motor oil grades for colder conditions

Motor vehicle manufacturers and oil companies invest millions in motor oil grades that work under wide-ranging climatic conditions. The result is the virtually fit-and-forget reassurance that we enjoy as year-round vehicle operators – whether driving artics in the UK, tractors in Germany or hatchbacks in Hammerfest, above the Arctic Circle. While you should understand the importance of the right motor oil grades for colder conditions, the good news is that oil companies and manufacturers make it easy to make the correct choice…

Why ‘different’ motor oil grades are required

It’s all down to viscosity – the ‘stickiness’ of lubricants. Oil must be viscous enough to protect moving parts, yet not too ‘sticky’ that it saps power. Oil must also allow a starter motor to turn an engine fast enough to start at the lowest ambient temperatures – yet have enough viscosity for adequate lubrication at a designed operating temperature that’s same for the tropics or the Arctic. The same principles apply to car, tractor or commercial vehicle lubricants.

Modern multigrade engine oil holds the key

Multigrade oils are identified by their ‘W’ (Winter) prefix: 5W 20, 10W 40, 15W 40 and other grades. They consist of polymers added to light base oils to prevent excessive thinning at higher temperatures. When cold, the polymers stay coiled so the oil flows better. But as the temperature rises, the polymers unwind into long chains that reduce thinning. This maintains the viscosity required at normal operating temperature. It’s clever technology and it means we don’t usually have to change between single-grade oils with the seasons.

All you need to know is in your vehicle manual

Do you remember the last time you looked through your vehicle’s operating manual and saw the little chart showing temperature ranges and engine oil grades? That chart holds the key to easy starting and correct lubrication wherever you use your vehicle. It’s called an Ambient Temperature Against Oil Viscosity Chart and it shows the correct grades of automotive oils for different climatic conditions. All you need to do is find the lowest expected ambient temperature at which your vehicle will operate, then read off the manufacturer’s recommended oil grade.

The secret to using the right oil

By following this advice, you’ll be covered for the range of temperatures described. The manual will have been written for the country where the vehicle was sold – and of course, the oil companies work closely with manufacturers to match engine oils to climatic regimes. And if you move your vehicle from North Africa to Norway? Just consult the handbook, your local manufacturer’s representative or your oil company for advice.

Relax! You’re protected no matter how cold it gets

The miracle of multigrades means that seasonal oil-grade changes are a thing of the past for most users. To keep your car, truck or agricultural vehicle correctly lubricated, all you need to do is read its manual, ask the manufacturer or call a reputable lubricant manufacturer. Then relax and enjoy using your vehicle in the knowledge that it’s protected by one of the correct automotive or agricultural oils regardless of how cold conditions get.