As soon as the summer begins to spool down, it’s best to take stock of your vehicle maintenance program with an eye toward handling the winter months. After all, the worst time to be prepping for cold weather is during cold weather.
Here’s an essential list of things you need to think about, including what parts of your vehicle need attention, a quick look at diesel winterization, and finally, a comprehensive emergency ‘on-the-road’ package, just in case something does go wrong.
Why Is Winter Car Prep Necessary?
Just like prepping for hot summers, getting ready for winter is about staying ahead of problems instead of scrambling when something goes wrong. The season brings its own challenges like snow, ice, and shorter days—making working lights, brakes, and tires essential for staying safe on the road. On top of that, the cold itself is hard on your vehicle. It drains battery power, thickens oil, and pushes antifreeze to its limits, all of which can lead to hard starts or breakdowns. And in some states with harsh winters, equipment like snow tires isn't just smart, it's the law. In short: a little prep now keeps you safe, reliable, and road-legal all season long.
Important Winter Maintenance Checks
Winter prep doesn't have to be a weekend-long project. These checks cover the systems that take the biggest hit from the cold, and most of them take just a few minutes.
Tires
As noted, in some areas, dedicated winter tires are necessary to safely manage winter travel. However, even if you’re not planning to swap out your rubber shoes, there are certain maintenance steps you should take before temps drop.
- Check your tread depth. Deep tread is key to gripping snowy roads. Use a tread depth gauge or the penny test: insert a penny into the tread groove with Lincoln's head facing down. If you can see the top of Abe's head, it's time for new tires.
- Watch your tire pressure. Cold air contracts, so your tires lose pressure as temperatures drop. Underinflated tires mean less grip and responsiveness on ice and snow, plus poorer fuel efficiency and extra wear. For the most accurate reading, check pressure in the morning before you drive, since driving warms the tires and temporarily raises the pressure.
- Look for uneven wear. Wear that's heavier on the edges, center, or one side of the tread can signal pressure, alignment, or suspension issues worth fixing before winter. Not sure what you're looking at? Our guide to interpreting tire wear patterns breaks it down.
Battery
The chemical reactions that take place inside a battery slow down in the cold, which can lead to reduced electrical output and—you guessed it—the dreaded click-click-click upon startup. Additionally, all those extra power loads you’re running, like the heater, defroster, headlights, and wipers, are placing added stress on a cold-weakened battery.
To ensure everything performs as intended during the winter, give the battery a quick but thorough inspection:
- Inspect the terminals. Look for corrosion on the terminals and cables, and clean off any buildup with a baking soda and water solution.
- Test the voltage. A multimeter will tell you whether your battery is healthy and fully charged. A reading around 12.6 volts is ideal, while anything below 12.4 means it needs a charge.
- Know when to replace it. Most batteries last three to five years. If yours is in that range or has been slow to start, swap it out before the cold makes the decision for you.
- Check the charging system. If you're comfortable, inspect the alternator and belts for corrosion, wear, cracking, fraying, or glazing. Not sure what to look for? A mechanic can handle this check for you.
- Listen and watch. With the engine running, note any squealing or whining noises and keep an eye out for dashboard warning lights.
Fluids
Ever leave a bottle of water or, worse, a can of soda in your car’s cupholder overnight when temperatures plummet? Now imagine that happening to the fluids inside your engine or radiator. Since cold temperatures can lead to freezing, it’s important to ensure car fluids like oil, antifreeze, washer fluid, or diesel fuel are being kept at the right viscosity:
- Follow the schedule. Swap out fluids according to your vehicle manufacturer's recommendations, and keep everything topped off for optimal performance.
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Check for leaks. Cold temperatures only make leaks worse, so now's the time to find them. Our article on fluid leaks covers what to look for and how to address them.
- Switch your washer fluid. Standard washer fluid is mostly water and can freeze in the reservoir, hoses, and nozzles, leaving you stuck when your windshield needs it most. A winter-rated blend will keep it flowing.
Visibility
Speaking of windshields, being able to see clearly is a must in winter weather.
Start with your wipers. If they're streaking or skipping, consider upgrading to silicone or winter-specific blades. Silicone holds up well in the cold, and winter blades have a sturdier, more flexible design and protective coatings that help them shed snow, slush, and ice instead of freezing up. While you're at it, check the windshield itself for chips or cracks, since cold temperatures can quickly turn small damage into big problems.
Being seen matters just as much as seeing. Walk around your vehicle and make sure your headlights, taillights, brake lights, turn signals, and hazards are all working and bright. If your headlights look dull or the housings are cracked or faded, now's the time to repair or replace them.
Cabin Comfort
Considering it's where you spend every minute of your drive, your vehicle's cabin belongs on your winter prep list too. Before temperatures drop, test the heater and defroster to make sure they're working well, and get any issues fixed.
It's also worth adding some interior protection to keep things clean and comfortable. Heavy-duty floor mats not only keep your carpets from turning into an unsightly, soggy mess, but also protect your floor pans from rust caused by moisture and road salt. Similarly, seat covers help guard against weather damage, while truck bed mats and cargo liners keep winter messes contained.
A Note on Diesels
Before we get to what emergency elements are necessary to protect you and your vehicle, let’s quickly discuss diesel winterization, since this engine type requires some additional cold weather prep.
First, it’s important to remember that diesel fuel will gel up in very cold temperatures so you must always use winter-grade diesel fuel. In extremely cold climates, it's a good idea to use a fuel anti-gel additive, which can further lower the gel point of diesel fuel and prevent filter clogging.
Second, diesels can struggle with cold starts, so ensure that glow plugs or grid heaters are functioning correctly and take note of any extended cranking times or difficulty starting. Consider using a battery blanket or engine block heater as well, to further assist with cold starts.
Lastly, remember that Diesel Exhaust Fluid (DEF) has a freezing point of approximately 12°F (-11°C) and, when frozen, can lead to serious issues with your vehicle’s emissions system. Many modern diesel vehicles are equipped with a DEF tank heater to prevent this from happening, so just ensure this heater is functioning correctly before cold weather strikes.
Emergency Prep
Below is a list of items you may wish to keep on hand this winter, depending on how bad conditions get where you live. Prepping this kind of setup is largely subjective, and more times than not limited to available carry-on space, but you’d be surprised how many of these supplies can neatly fit into one large duffel that sits in the trunk.
- Blankets and warm clothing
- Flashlight with extra batteries
- Non-perishable food and water
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First Aid kit + backups of important daily medication
- Multi-tool or knife
- Portable jump starter
- Ice scraper/windshield brush
- Reflective triangle or flare
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Traction mats, tire chains, or a bag of sand/kitty litter
- Shovel
- Paper map in case GPS fails
- Spare cash
- Toilet paper (trust us on this one)
Winter-Ready Starts With Parts Via
Checking these systems now means fewer surprises once the snow starts falling. When your inspection turns up something that needs replacing, Parts Via has you covered with quality parts and accessories from trusted brands. Plus, you can enjoy FREE fast shipping when you choose "Ship to Store" at checkout. Take on winter with confidence, courtesy of Parts Via!