How to Winterize Your Car, Truck, or SUV: Winter Is Coming!
Winter is a harsh season on your car as the temperatures drop, and that requires that you “winterize” your car to protect it.
It would be great if we could just drive our vehicles and never have to worry about what the weather will do to them. Unfortunately, reality dictates that we need to make sure our cars, trucks, and SUVs are ready for what Mother Nature is going to throw at them. When the air gets chillier, you need to make sure your ride is ready for the colder temperatures. We’re going to explain just how you winterize your car before failing to winterize your car makes you have a bad day.
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Wait, Cars Can Freeze?
Well, yes and no. For your coolant system—which we’ll get into later—if you’re running straight water for the best cooling you can get during the summer, that water will freeze. For other fluids, such as oils and grease, their viscosity—the thickness of the fluid—will change. Typically, the colder the temperature, the higher viscosity that fluid will have and the less freely it will flow.
Engine oil is formulated differently, as its viscosity is lower at cold temperatures (the number before the W you see on the bottle) and gains viscosity as the engine reaches operating temperature where it plateaus (the number after the W), typically around 120 to 180 degrees. That’s also why it’s still somewhat important to warm up your car, but typically by the time you start it and drive to your first stop, it’s already warmed to operating temperature.
Is Winterizing a Modern Car Necessary
The way a car is made and how much technology it comes with don't eliminate the effects of winter on your vehicle. Winterizing a car is still necessary, but the need for much of what used to be done in the past has fortunately been reduced. There are fewer points that need greasing or fluids that need changing thanks to longer-lifespan fluids, but some items still need to be changed, replaced, and maintained.
Can You Prevent Freezing Without Maintenance?
In short, no. Physics and thermodynamics aren’t easily defeated. Your only bet is to park in a temperature-controlled garage or some sort of parking space that prevents freezing thanks to insulation or heating. Otherwise, a car exposed to the elements will “suffer” from them when not in use.
When Should I Winterize My Car?
The best time is during the late fall, but a timeframe between late November and into early December is the latest we’d push it, depending on your climate. If you live in a place that remains warm year-round and the temperatures never drop below freezing, you can get away with doing this very late or possibly not at all. However, we’d argue you should still do it as it’s a part of regular maintenance, which will prevent you from suffering potential damage to your vehicle if you happen to venture into an area that does see freezing temperatures (such as high altitudes for a Christmas vacation).
Where to Start? Basic Maintenance
The first thing you should do is any and all basic maintenance that’s due for your vehicle. Yeah, it’s a pithy first step but one that is critical for every car out there. For ICE vehicles and hybrids, this includes fluid changes, but every vehicle (including BEVs) will need a tire rotation to make sure you’re literally putting your best foot forward when the roads get slick and covered in snow. Well, unless your car is FWD, then you’ll want to put those better tires on the back axle. Because it isn’t being driven, having as much grip in the rear is crucial for those vehicles that drive the front wheels.
Winter Tires
Speaking of tires, if you’re in a climate that regularly sees temperatures at or below freezing, you might want a set of winter tires. This isn’t a gimmick: Winter tires are made from a softer compound of rubber, and that’s because of the drop in temperature. As it gets colder, the compound of the tire rubber becomes harder and reduces the mechanical grip they provide because they become less and less able to conform to the microscopic imperfections of the roads you drive on.
Change Your Wiper Blades
It’s better to do this during the fall season changeover, but if you haven’t changed your wiper blades, this is the time to do it. A fresh set of wiper blades helps clear your windshield of snow or sleet or rain more effectively. If your car is exposed to a very sunny environment, the UV light will break down the rubber of your wiper, causing it to crack and stiffen. This not only leads to degraded wiper performance but can also lead to the wiper skipping, as it no longer has the elasticity to conform to your glass. Yes, you must also regularly change the wipers on your headlights and back window if you have them.
Checking Your Coolant
You’ll want to check the coolant to make sure it’s ready for the colder temperatures your vehicle is about to face. Straight water will freeze at 32 degrees Fahrenheit, but the coolant and its additives will prevent that freezing air from freezing the water found in your engine block, head or heads, heater core, radiator, and all associated lines. The freezing and blocking the flow of fluid in those items are bad enough, but the real risk comes from the water expanding when it freezes. This will crack or rupture coolant passages, tanks, and hoses.
Yes, This Does Include (Some) EVs
While you might think EVs are safe from this, not all are, as there are fluid thermal management systems out there. Two EV are safe from coolant checks. The first is the Nissan Leaf and its air-cooled battery pack and motor. The other is the BMW i3, which uses its air-conditioning system to cool its battery along with the cabin area.
A Holiday Mix
For everything else, those liquids will need to be changed, and you’ll need to ensure their mixture is correct to prevent freezing when the vehicle isn’t being used or charged, in the case of EVs and PHEVs. All liquid coolants used—even in liquid-cooled EVs—are a solution of ethylene glycol and water in a 50/50 ratio. Before you panic, you’re not driving a fire hazard with a water-based cooling system with a lithium-ion battery pack. The ethylene glycol content makes the water non-conductive, but that’s also why you should always make sure that your EV’s coolant is topped off with a premix.
You’ll also need to monitor its mixture over time, just as you would an ICE-powered vehicle. That 50/50 ratio should be treated as your minimum here, but adding more ethylene glycol won’t hurt so long as the ratio isn’t more than 60/40, with 40 percent being water. This does allow for the outside temperature to be lower before your coolant freezes, but going with too much ethylene glycol will harm your cooling performance and cause the temperatures to rise in your engine and battery pack. If you want to bring any coolant back or closer to 50/50, you must use distilled water. Regular tap water contains impurities that can deposit in your cooling system and not only reduce cooling performance but also damage the pumps that circulate that coolant, so it should be avoided.
Having experience in many forms of the automotive industry, Justin Banner has done more than just write about cars. For more than 15 years, he's had experience working as an automotive service technician—including a stint as a Virginia State Inspector—service advisor, parts sales, and aftermarket parts technical advisor (a fancy way of saying he helped you on the phone when you had trouble fitting your brakes over your aftermarket wheels and the like). Prior to his tenure as a full-time editor, Justin worked as a freelance writer and photographer for various publications and as an automotive content creator on YouTube. He’s also covered multiple forms of motorsports ranging from Formula Drift, drag racing, and time attack, to NASCAR, short course off-roading, and open desert racing. He's best known for breaking down complex technical concepts so a layperson can more easily understand why technologies, repairs, and parts should matter to them. At MotorTrend, Justin is part of the news team covering breaking news and topics while also working as a judge for MotorTrend Of the Year events and other major comparison tests.
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