How to Prevent Winter Rust

One thing is very apparent about cars that live in snowy, winter climates of the Midwest and above – RUST. Take a trip to the southern United States, or out West, and suddenly, rust on cars begins to disappear. Many things are harsh about winter. Not only can winter weather put a damper on your own mood, but it can be difficult for your vehicle to deal with as well. While you may be getting into the car, turning on the heat, and shivering while your car warms up and wishing for warmer temperatures, your car may feel the same kind of way.

One of the most difficult aspects of winter driving is protecting your car against winter road treatments. Of course, nobody wants to drive on black ice and packed snow, and this is why cities, municipalities, and states take it upon themselves to apply road treatments to make sure that snow and ice do not build up and cause accidents. The most common road treatments we have come across are usually salt-based (either liquid or rock-form) sand, or a mixture of the two.

While there is no doubt that these road treatments prevent many accidents, it's also no secret that they are hard on your vehicle. People have known this since way back during the days of the Model T, where drivers would actually apply used motor oil to the undercarriage of their cars to protect the chassis against road salt.

How to Prevent Rust from Road Salt

1. Clean It Up

It’s important to understand that the very presence of salt on the road isn’t the main issue – it’s salt that melts the ice/snow, and becomes salt water that splashes into every nook, cranny, and crevice on your car. The first defense against salt is to ensure that your vehicle is cleaned as often as necessary. Many people forgo washing their car in the winter until that one nice day when it hits 40 degrees, and suddenly the car washes are packed. Wash your car often. Way too often. Try to seek out a car wash that does undercarriage washes as well, as these help flush the salt out from the bottom of the car. Generally, rust starts when saltwater and muck get into areas that are not commonly washed, or cannot dry completely easily. From there, the problem gets worse, and worse, from the inside out, until suddenly, you have a bubble in the paint, and then a rust hole.

If it is too cold where you live to get out and wash your car, it’s a good idea to at least take your vehicle through a professional car wash every week or two in the winter. It is true that doing it yourself generally results in better work, but if you cannot get out on your own the touchless car washes are better than nothing. Depending on the driving conditions where you are, however, once every two weeks may not be often enough. You can forgo the washing as much when the roads are clean, but when there is snow and salt present – wash often! Keep in mind, self-serve car washes (those ones that you put 2.00 in quarters in to use – correction – 2.50 because it eats 2 quarters and doesn’t give them back) are a great solution in the winter. Keep in mind, you’re not aiming for your car to be showroom clean. Chances are, it’s going to be dirty again in a day. In a self-serve wash, you can blast and clean the fenders, in the wheel wheels, the under the rocker panels, and get all the areas where salt lives and settles.

2. Wax It On

Before it gets too cold to even think about being outside, you want to give your car a solid waxing. Just like waxing your car protects it from UV rays in the summer, it prevents corrosion from road treatments in the winter, at least on the outside. Generally speaking you are going to want to re-wax your car once every 3 months during the winter.

3. Knock It Off

In between car washes, especially when there’s snowy slush on the ground, your car can build up massive “slush jams” in the wheel wells and other areas. If you are not able to take the car to a car wash during this time, you should do a little bit of maintenance between washes to make sure that this salt/slush combo doesn’t sit on your car, or worse yet, completely freeze into solid blocks of ice when the temperature really drops. Try to knock out any solid packed ice or snow slush from the wheel wells, or rocker panels under the door. To do this, you can use the blunt-end of a sturdy ice scraper, or even the back of your heel if it’s on the rocker panel or fender edge. Some folks will carry an old broom handle or other “poking” device to knock these jams out.

4. Look Underneath

Of course, it figures that the easiest bits of your car to keep clean are also the ones that are actually least susceptible to corrosion. You still want to make sure that the body of your car is well-maintained, but the part of your car that is actually most at risk is the undercarriage. Like stated before, getting the bottom of your car clean is crucial. Whether you do this in a self-serve car wash by getting the pressure wand under the car as best you can, or seeking out an undercarriage wash, be sure you do it!

There are also specific products that can be used on the underside of your car to prevent it from experiencing corrosion due to splashback while driving. Fluid Film is one of these products, and is designed specifically for this. Fluid Film sprays on a liquid, but has a semi-permanent waxy coating that resists water and anything that water may be carrying, like salt. In the months leading up to winter, raise your car, climb under and spray the inside of the rocker panels, frame or subframe rails, inner edges of the fender, or anywhere salt or saltwater could splash. Remember, cracks or crevasses are the worst for trapping salt water. Look them over carefully, and spray with Fluid Film. Generally, when inspecting a used car at purchase that’s over 8 years old, you will really quickly be able to tell that one of two things have happened from the underside of a car – either it was well taken care of by washing in the winter, or the car spent it’s life outside of the rust belt.

5. Look Inside

While it is true that the inside of your car is not going to experience corrosion as a result of salt treatments on the road, these substances can also be very problematic for your carpets as saltwater can not only ruin your carpet, but trapped in the carpet can rot your floorboards from the inside out. Probably the most common way to deal with this is to purchase winter-specific floor mats for your car. The best kind of floor mat when it comes to dealing with winter weather debris are rubber ones that function as trays. These can be easily installed and hold any drippings from your shoes until you can remove them and dump them out. There are many manufacturers of both universal floor mats that can be cut and trimmed to fit, or direct-fit floor mats like Weathertech. Going into spring, you may simply remove these mats and replace with your original carpeted “summer mats”.

If you are not able to invest in rubber mats for your vehicle, be sure to frequently lift the original mats and check for water. It’s highly recommended you have some sort of car mat in the winter, or a piece of plastic at best. If you find water in the carpet, it needs to be extracted and dried quickly.

If you suspect that you have soiled carpets from either saltwater, sand, or muck, the best thing to do is remove them from the car immediately if you can. These mats can be rinsed off at a self-serve car wash, or cleaned with a bucket of warm water and hung to dry somewhere like a bath tub (ask permission first!)

Taking care of your auto-investment is crucial in the winter time. Vehicles between the ages of 5-10 years old can rapidly deteriorate from winter use if not taken care of, which can ultimately result in several thousand dollars of loss between a clean, well maintained vehicle, and one that has rust issues.

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