How to Protect Your Car From Sun Heat (Interior & Exterior)

We’ve all, on occasion, returned to our cars to find them sweltering in the summer heat. I’ve had to air out my car before driving it more times than I can count. So I thought that we should have a conclusive guide to protecting our cars from sun and heat damage we can look back on when the sun decides to grace us with its presence again.

In the following article, I’ll talk about all of the best ways to avoid having to pay for sun damage repairs. But before I do, let’s talk about the negative effects that the sun and heat can have on cars.

How to protect your car from sun damage. Tips for interior, exterior, (paint), and under the hood.

What Happens If You Leave Your Car in the Sun?

Most drivers know to avoid the sun — but not everyone knows why. The sun can actually cause extensive damage to pretty much all of the car components. The rubber and plastic parts can melt and fuse the various metal panels shut. What’s more, the various liquids can simply evaporate, forcing you to use them up faster than you’re expecting to.

Exterior Sun Damage

If you leave your vehicle in the sun for long enough, you can even see some color fading. Although, I should say that the color fading is primarily an issue for vibrant or dark paint. It’s also fairly easy to take care of with wax or a paint protection film. But we’ll talk about that a bit later.

Another type of exterior damage can also affect the rubber gaskets around your windshield and the car doors. In extreme situations, when the car hasn’t been moved for a while, the doors can even get fused shut.

After all, the temperature of the surface of your ride can reach up to 200 degrees Fahrenheit. That’s almost the temperature of boiling water! And though rubber has a higher melting point of about 260 degrees, it can still shift in that kind of heat. That’s mostly going to come into play later on when you discover that your windshield is now leaking water.

Interior Sun Damage

Like the exterior of a vehicle, the interior can also sustain much damage, including color fading. The dashboard plastic can also crack or bend in the heat — and it can even be uncomfortable to hold the steering wheel or even sit.

On hot summer days, it can actually get to 145 degrees Fahrenheit inside a car. At those temperatures, you shouldn’t only worry about your ride — you should also watch your skin.

People routinely singe the back of their thighs by sitting directly on their car seats in the summer. But what are we supposed to do, wear longer and thicker layers in the summer?

And that’s not even mentioning what can happen if you accidentally leave the wrong thing in your vehicle. One time, I returned to my car to find a suspicious smell in the cabin and pieces of colorful plastic scattered across the floor.

As it turns out, my friend had accidentally forgotten his lighter in the car and the greenhouse effect had done the rest. The gas in the lighter expanded in the heat, making short work of the already weakened plastic shell. Can you imagine that happening while you’re in the driver’s seat?

While this was certainly one of the more explosive examples of what can happen inside a hot car, it’s not the only one. I’ve found melted water bottles in my car on more than one occasion, even when I’d parked it in the shade.

Engine Issues

Finally, we’ve reached the crux of the matter. Your engine needs oil to run smoothly, and if your car gets overly hot, it can cause the oil to evaporate or cause structural damage through which it can start to leak out.

Additionally, your vehicle needs transmission fluid to allow you to shift gears smoothly and keep the transmission cool. Furthermore, during the summer, you also need to keep a close eye on the coolant liquid. All of these things can evaporate in hotter temperatures and cause serious malfunctions in your car. Fortunately, they’re all easy enough to prevent.

Now, if the choice is between having to make reparations or setting up preventative measures, I’m always going to go for the latter. So with that in mind, let’s see what steps you can take to avoid needing to reverse the effects of sun damage are.

Tips for Protecting the Exterior of a Car

When you think about it, all of the negative effects of the sun start with the surface of the car. As I’ve previously mentioned, the exterior of your car can get almost as hot as boiling water if you leave it in the sun on a particularly hot day. So here’s the most logical thing you can try to avoid paint fading.

Keep It in the Shade

The one common-sense piece of advice all drivers naturally know is to keep their ride in the shade. This decreases the chance of it suffering under the sun for too long.

But let me just tell you — that shade is elusive! Not only is it sometimes impossible to find, but it’s also kind of fickle. Naturally, shade moves with the sun, so you may find your vehicle under the full blast of the sun even if you had parked in the shade.

If you want to avoid this at all costs, you can find an underground parking structure if one is nearby. Also, if you know you’re going to leave your ride outside for long periods of time, you may want to get a car cover as well.

Wash Often and Hand Dry

High temperatures can fuse all of the dust and residue onto the surface of the vehicle. Between the regular debris and the bird excrement, the dirt on your car could cause serious damages to the paint or the clear overcoat. So if you want to avoid having to get a new coat of paint, you’re going to need to wash your car often.

Furthermore, manually drying it is also very important, at least if you’re washing it outdoors. After all, dust will settle onto the wet surface before you’ve even had a chance to take a photo of your squeaky clean ride.

Apply a UV Protection Wax

After you’ve done such a great job cleaning and drying your vehicle, you can add a few coats of automotive wax. Some of these products can actually provide your paint with long-lasting protection. For example, this CarGuys Liquid Wax has a built-in UV ray protection.

Use it on your paint, glass, and rims — just rub it in with the applicator pad that comes with the wax. The wax also comes with a microfiber towel you can use to dry the car off before applying the wax.

Consider Paint Protection Film

If you don’t think that wax is enough protection against the damaging ultraviolet rays of the sun, you could opt for another type of physical barrier. Paint protection films are much more difficult to install than applying wax. They can be in a roll, like this VViViD 3M Clear Paint Protection Vinyl Film, or cut up in ready-to-install pieces. Either way, you’ll probably need a professional to apply it.

Still, some people do prefer something like this to defend against scratches and paint fading. In fact, it would even make it easier to get rid of bugs and road tar. However, I should mention that this really won’t protect you from the heat, which is what we’re trying to curtail.

Check Tire Pressure

As you may have guessed, hot temperatures are also going to affect the shape of your tires. Generally, with every 10-degree Fahrenheit increase in temperature, the tire pressure will also increase by 1 psi. Although low tire pressure is much more dangerous than high pressure, there are still disadvantages to driving on overly taut tires. Namely, taut rubber is easier to puncture and damage.

So you may want to keep a tire pressure gauge in your glove compartment during the summer. That way, you can check in on your tires regularly or when you feel them performing badly. And most importantly, you can fix the issue immediately.

One way to protect the car interior is by cleaning it regularly.

How to Protect the Interior of a Car From Sun

Obviously, the interior components of your ride are the ones that are going to suffer the most. All of that heat passes right through the metal and the glass shell of your car to create the perfect storm on the inside. If I told you how many pets have suffered a heat stroke because their owners had left them inside the car on a hot day you’d be absolutely horrified. So I suppose the first step here would be to avoid doing that.

That aside, the interior of your vehicle would also be fine if you parked in the shade. Still, if you can’t do that, your interior will likely do much better than your exterior with a few sun protectors. And another thing you could do to keep your car cool is to clean the inside of the car before cleaning the outside.

Clean the Inside of the Cabin

Just like I explained when we were talking about the exterior of the car, the interior can also get crusty and disgusting under the sun. Naturally, no one wants to see that. If you want to prevent that, you could just keep a microfiber cloth in your glove compartment and swipe over the dashboard once in a while. You can use water to scrub away the grime or, even better, car interior cleaners.

However, you should also give your vehicle a deeper cleansing once in a while. Get your carpets and floor mats out from under the seats. If the heat’s been really intense, they could have even fused together. You can either get new ones if you feel like you should or read this article to see how to clean them properly.

While the floor mats are drying, you can declutter and vacuum the car as well. All this will just get rid of the nasty gunk that can leave stains or cause unpleasant odors.

Use a Windshield Protector

As someone who lives in an area where summers can be pretty unforgiving, I can tell you that windshield protectors are going to be your best friend. These huge foil covers go right under the windshield glass, covering the entire surface so that the heat won’t be as bad when you return to the car.

Additionally, windshield protectors will prevent any other sun damages in most of the other areas of your car. Best of all, there are all sorts of fun options on the market, so you don’t even have to stick to the regular foil protectors.

Get a Dash Cover

Still, a windshield protector will only protect your dashboard while your car is parked. However, you could also get a dash cover to protect your dash from fading while you’re driving.

Additionally, dash cover mats, like the one I’ve linked to, could significantly reduce the sun glare that hits the dash, thereby bringing the internal temperature of the vehicle down. This is an especially good option for the people who spend a lot of their days in transit. Truckers and taxi drivers, for example, should invest in dash covers.

Put up Window Shades

Of course, the passengers would also be relieved if you had some sun shades in your car as well. In fact, you could also leave them on your windows when you park. Between the windshield protector and window shades on every window, you’d be greatly reducing the amount of unfiltered sunlight that gets into your vehicle.

Install Seat Covers

As I’ve said before, there’s nothing worse than getting into a stiflingly hot car on an already humid day only to get the back of your thighs singed off. That’s why having a good seat cover is so important.

Now, seat covers are a pretty personal choice for a lot of people, so I’m not going to recommend one of them. After all, it’s mostly about esthetics. Besides, different car models have different seats, so seat covers aren’t generally universal.

However, I do recommend using some sort of seat cover or at least a fabric protectant. If you have leather seats or another type of fabric that can be hurt by prolonged exposure to the sun, there are all sorts of commercial conditioners you can try to prevent cracking.

That being said, I am going to point out a seat protector I found interesting. The Modokit seat protector is essentially a waterproof towel. You can keep it in a roll in your glove compartment until you need it and wash it whenever you need to. The cover will protect your thighs from singing, and it even comes with two window shades.

Install Thermal Insulation

Of course, the ultimate solution for internal heat damages would be to use thermal insulation products. Noico makes a lot of automotive thermal and sound insulating products. Their products are one of the most popular ones.

I recommend using these insulation mats under the hood and maybe even elsewhere. Keep in mind, you will need to remove your headliner in order to get this up there. So ask a friend or a professional car mechanic to help if you’ve never done this before. Still, this could be a great way to keep things under the hood cool.

Protecting the Engine From Sun Heat

If you install thermal insulation under the hood, you should be pretty much set for the summer. However, there are still some things you’ll need to keep an eye on throughout the season.

I’m talking, of course, about checking the various fluid levels under the hood. Motor oil, transmission fluid, power steering, and brake fluids are all incredibly important for the functioning of the car. You should always know what type of each of these fluids your car uses and have them on hand in case you need to replenish them.

Car Battery

Since heat often causes battery fluid to evaporate, you’re going to have to check in on the car battery often. It’s best to avoid having to repeatedly charge the battery since that would significantly shorten its lifespan. However, just because a battery is misbehaving in the summer, it doesn’t mean that heat is the reason why.

The issue could also be caused by a bad starter, so make sure that you know what you’re dealing with. Keep checking the fluid levels just in case, and take it to a mechanic if you notice something wrong. You should also test the battery a few times during the summer somewhere where you can replenish its electrolyte levels.

Cooling System

You really don’t want your coolant to fail you in the middle of summer. So this is one of the things you’ll need to drain and replenish by the book. And by that, I mean the car’s manual.

And while the coolant keeps your engine cool, you’ll ideally be under the car’s AC. If you notice that the AC is malfunctioning, you can take the car to a mechanic. They may be able to change the refrigerant charge level or fix anything else that comes up. Also, if you’re not feeling the AC as much as you’re used to, one of your windows could be letting air in. However, those issues are typically easy to fix with a good window sealant.

Air Filters

Lastly, if you want to keep the air inside your vehicle cool and breathable, deal with your air filters. Because of all the dry dust outside the car, your filters may be more clogged during the summer than they are during colder months. And dirty air filters won’t just affect you in the cabin — they’ll also affect the car.

Final Thoughts on Automotive Sun Protection

No matter how much we all love basking in the sun, most of the time, it’s really not our friend. So do for your car what you should be doing for yourself as well — sunproof it!

Keep your ride clean and check in on the general condition of the tires and the fluids it needs to function all throughout the summer months. You can give it a good waxing at the beginning of the season and use the interior sun protection shields. If you follow all of the tips I’ve explained in this article, you’ll have nothing to worry about until winter.


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