Winter season weather, freezing cold and heavy snow make the driving experience a lot more complicated. The good part is you can prepare beforehand to avoid a lot of unpleasant situations. It’s like the saying, there’s no such thing as bad weather, only inappropriate clothing.

Good to know cars don’t need any clothing but there sure are things that must be checked. This time we would like to share valuable tips that every driver should know for preparing the car for the coldest season to enjoy safe travels on the road.

Check the condition of the tires

Even the best car is of no use without its tires, and good tires are especially important in winter. It is recommended not to use tires older than 5 years, as the rubber has hardened, which means the tires have already lost their properties. But most importantly the tires’ pressure needs to be at the correct pounds per square inch (PSI). In cold weather tire pressure decreases around 1 PSI when the temperature drops every 10 degrees. It doesn’t mean you’re losing pressure - it means the air is taking up less space.

Your tire pressure standardly needs to be 30 to 35 PSI. Keep in mind that this number doesn’t change all year round. Although, you need to check the tire pressure more frequently since it deflates much faster in winter. Here comes in handy OBDeleven for the BMW Group vehicles, allowing you to display Tire Pressure Monitoring System on your multimedia screen. This feature can be activated with the One-Click App which saves you a lot of time because there’s no need to check the pressure manually. Before activating this feature, make sure your vehicle is equipped with the Tire Pressure Monitor System (S2VBA) and NBT or NBT EVO Navigation system Professional (S609A).

Change the oil

The negative temperature has a serious effect on oil – it starts to flow slower or sometimes doesn't flow at all, putting a lot of pressure on the engine.

When you’re buying oil, you should know that oil is measured by its viscosity which means how thick or thin it is. The higher the viscosity is, the slower the oil flows. Since the oil gets thicker with a negative temperature, you have to make sure it can run smoothly. All oils have a rating – the number before the W says the viscosity of the oil at a negative temperature. The lower the number is, the thinner the oil and the better performance at minus temperature.

Also, there are two types of oil – regular oil and synthetic oil and it’s important to know their difference.

- Synthetic oil holds up better in higher and lower temperatures compared with regular oil.

- Synthetic oil moves with less friction through the motor which results in better horsepower and engine efficiency.

- Regular oil is not a good lubricant compared to synthetic oil, so synthetic oil extends the engine’s wear protection a lot.

Don’t forget that using OBDeleven for Volkswagen Group (VAG) vehicles, such as VW, Audi, Škoda, or Seat, you can set a reminder to change your oil, so you won’t forget the last time you changed it.

Change the fuel filter

Diesel engines need extra maintenance in the winter season. The crucial thing to help your car to start and run smoothly is to have a clean fuel filter. It gets easily clogged particularly in winter when the temperature drops below 4°C degrees.

Diesel fuel starts to gel up, so it doesn’t get through the filter as easily and has difficulties starting up. It can even happen the car doesn’t start simply because of the fuel filter. That’s why we recommend changing the filter before winter. Although, as a dutiful driver you should already know that most diesel fuel filters should be changed every 10,000 miles (~16 000 kilometers), so once a year is perfect for the average driver.

It's worth mentioning that all diesel-powered cars and trucks built since 2010 require diesel exhaust fluid. Due to specific pollution regulations engines are being equipped with catalytic reduction. Diesel exhaust fluid is used as a consumable in SCR to lower NOx concentration in diesel, so the exhaust emissions are less toxic. This brings another problem: diesel exhaust fluid freeze solid when the temperature is 12 degrees Fahrenheit or less because it’s a water-based liquid. A lot of cars have diesel exhaust fluid tank heater that thaws the liquid. So check if yours has one, or make sure you have enough amount of diesel exhaust fluid on hand.

Examine the battery health

Cold weather is a silent killer for your battery. To be specific, it could drain your battery power by 30-60%. Even though the battery naturally charges when driving, the first thing you got to do is to get it started. With OBDeleven you can simply avoid this problem by checking the battery status with the mobile app or by setting the battery charge level display on your Volkswagen Group (VAG) vehicles’ instrument cluster. This feature lets you check the charge level of your battery, so you will be always aware of your car’s battery health.

What’s more, it is recommended to check or even replace terminal ends. It’s quite common that a car doesn’t start because terminal ends are covered with corrosion. This happens much more often in winter compared to summer, so sometimes it might not be your battery’s problem that the car doesn’t start.

Change summer windshield washer fluid to winter

There isn’t a thing called universal windshield washer fluid, it’s summer and winter windshield washer fluids for a few reasons. Summer fluid contains a higher amount of detergent to clean heavy dirt and insects much better, while winter fluid contains a high concentration of alcohol, so it doesn’t freeze when the temperature drops below zero.

We wouldn’t recommend mixing these two together because when you dilute a fluid that doesn’t freeze to -35°C degrees with summer liquid, the mix can freeze when the temperature is -15°C. This can result in unpleasant situations when the washer fluid freezes the whole system or even breaks it. And there’s no easy way out of this, you would have to leave your vehicle in a very warm garage for a few days, so the fluid thaws.

All in all, your winter season is a time when your car needs extra maintenance. With the right preparation, your travels will be much safer, and you will probably avoid those stressful situations when the car doesn't start.