15 Annoying Car Myths That Simply Refuse To Die

• Cars

As driving culture continues to evolve, one would expect knowledge to move with it. That is, what may have been correct for vehicles from the '70s doesn't have to be held dear in 2025. For instance, cross-drilled brake rotors may have been the best thing in the 1950s for bringing cars to a dead stop, but they are prehistoric today. Technology has long evolved beyond the need for cutting holes in metal, but the sentiment that cross-drilled rotors do the job best persists (partly because they are featured in sporty brands like Porsche and Lamborghini). This fallacy is a solitary example — many more myths about cars endure.

Some myths may hold water in specific contexts, others are outdated, a few are borderline fiction, and a couple might end up costing you a fortune. It's 2025, and it's time to put a few to bed. So, let's take a look at the 15 most annoying myths that just won't die.

Myth: premium gas is better for your car

Sports cars and a select few, like the Jeep Grand Wagoneer, recommend premium gas as the best fuel for their engines. Performance is a key part of the experience for speedsters, and the difference in octane rating between regular and premium gas can translate into slower acceleration.

However, that doesn't mean premium gas makes a difference for every car on the road. In the past, it was true that engines had octane specifications that they could or could not run on. Times have changed, though. Modern engines instead adjust their ignition timing via control systems to prevent knocking. You're only likely to notice the difference in premium gas over regular if you put pedal to the metal from a dead stop.

For cars that explicitly recommend premium gas in their manuals, you'd do well to heed the manufacturers; lower-grade gas could increase the threat of engine knocking. For the average Joe, premium gas isn't necessarily better for your car. SlashGear has covered even more fuel myths you need to stop believing. 

Myth: You need to warm up your car before driving

Idling a car is one concept that has refused to keep up with the times. The origin isn't that far-fetched to trace; depending on your age, you probably remember your parents letting the engine run for minutes on end before moving their cars.

This one's popular when the weather switches from hot to cold. Again, in the past, this statement held some water. Older cars needed oil to warm up and reach the necessary moving parts because the lubricant was thick. Skipping this process risked engine stalling. 

Fuel-injected engines changed the game in this respect. Lubricants flow much faster than before — your engine only needs about 30 seconds to get fully lubricated. The lubrication is more important to driving smoothly than the engine being "warm." You could easily achieve the warming goal by actually moving the car around instead.

Myth: You need to change your oil every 3,000 miles

One of the traditions of car maintenance culture in America is the 3k-mile oil change; car owners are encouraged to change their engine oil every 3,000 to 5,000 miles they drive. While this is applied as a rule of thumb, several factors determine whether oil needs changing or not. Engine type, oil type, and car manufacturer recommendations should be taken into account.

For instance, synthetic oil — which most new cars use – can run without problems for well over 7,500 miles. Some new models posit change intervals of up to 10,000 miles in their manuals, and others use oil life monitors to guide drivers on what their oil profile looks like. Despite these technological advancements, the 3,000-mile servicing rule persists.

This status quo can be attributed to drivers not wanting to rock the apple cart — if following the rule hasn't caused any problems before, it makes sense to keep practicing it. However, changing your oil twice or even thrice more frequently than necessary according to the 3,000-mile stipulation has real implications for cost savings.

Myth: Coasting downhill in neutral saves gas

In the face of rising fuel costs, it's only natural for drivers to look for ways to reduce their consumption. That's the basis for this myth — rolling a car downhill without the engine on. From a logical standpoint, if you give an object a push from the top of a hill, it'll slide down to the bottom without needing any extra force.

Apply that logic to cars, and you have the belief that cutting off the engine entirely will save gas. That's not true. Modern cars can detect when the vehicle is coasting, and in these situations, the Engine Control Module shuts off fuel supply while the downhill momentum keeps the car moving.

On the other hand, switching to neutral removes this ability. Instead of relying on momentum and conserving fuel, the engine continues to supply enough fuel to idle. By following the myth, at best, you use the same amount of fuel as if you left your engine running. In many situations, you'll even end up using more.

Myth: Driving without air conditioning reduces fuel consumption

The logic behind this myth is that using air conditioning puts a strain on the engine, and thus, cars use more fuel when the AC unit is running. However, while there's some veracity to this concept, it's not true in all situations. Fuel efficiency with air conditioning varies depending on driving conditions: the degree of conditioning, car speed, and aerodynamics.

A study from the US Department of Energy used a Toyota Corolla and a Ford Explorer (both manufactured in 2009) to illustrate the variability. At lower speeds up to 60 mph in the Corolla with the AC at 50% power, driving with the windows down was more efficient. For full-blast duty cycles, using air conditioning became more fuel efficient at around 75 mph. That's because at higher speeds, drag forces increase significantly.

The Ford Explorer yielded different results — using the air conditioner at full power used more gas at all speed levels, and at 50% duty, the car needed to be going at 80 mph for fuel consumption to be more efficient. In summary, fuel efficiency with air conditioning depends on the type of vehicle you have, but the blanket statement is false. SlashGear covered this debate in more detail.

Myth: Inflating your tires to max PSI can cause a blowout

Most car tires come with a recommended maximum pressure, a figure typically located on the sidewall. It's widely believed that, at this PSI, your tires are at a higher risk of encountering a blowout. This is because the max PSI on tires often exceeds the recommended amount stipulated by car manufacturers. At these elevated levels, car handling can be compromised, and stray potholes could cause a blowout.

However, this is a false perception. The burst pressure of a tire exceeds the max PSI by quite some distance; the max pressure simply indicates the pressure at which the tire will carry the most amount of weight. In fact, for specific vehicle types like SUVs, the car needs to be supported by the tires in proportion to the weight it's carrying — especially if the load is exceptionally heavy. To meet these load requirements, tires may need to be pumped to their maximum sidewall allowance.

You'll do well to be mindful of potholes, as mentioned earlier, and you don't want to go above the max PSI too much. Overinflated tires wear unevenly around the center, significantly reducing lifespan.

Myth: Electric vehicles are more fire-prone than gasoline-powered cars

Fires are scary, and one of the first cons you're likely to come across when researching EVs is fire risk. Part of this fear comes from their relative novelty to fire departments; EV fires last longer and are more difficult to put out. Where a regular gasoline-powered car takes between 500 and 1000 gallons of water to extinguish, a Nissan Leaf engulfed by fire in 2023 required 45,000 gallons.

Such incidents stick out in memory, but one must consider that it was that specific fire department's encounter with an EV fire. There are various ways to put out an EV fire, and current data estimates that it takes 2,500 gallons to extinguish an EV fire, on average. We've also covered the various ways to put out an EV fire. In terms of frequency, data from Sweden reports that EVs are actually much less likely to catch fire than regular combustion engine-powered vehicles.

According to the Myndigheten för Samhällsskydd och Beredskap, Sweden's public safety agency, about 600,000 EVs and hybrids were driven in Sweden in 2022. With an average of 16 EV fires per year, that's about a 1-in-37,500 fire risk. Gasoline-powered cars, on the other hand, have 1-in-1,300 odds of catching fire. Judging from these metrics, the sentiment that EVs are a greater fire risk is unfounded.

Myth: Pickup trucks are good in the snow

Snow is a tricky terrain to ride in. You could lose grip or get stuck, and even starting your car in the cold temperatures can prove challenging. For some reason, however, there's a belief that pickup trucks handle these adverse weather conditions better than any other vehicular type. On a surface level, pickup trucks do handle off-roading pretty well — they're sturdily built and have enough ground clearance to navigate obstacles that could cause problems for sedans or even SUVs.

The reality is a different story. Weight distribution is a problem for pickup trucks, given the physics of the truck bed being so much lighter than the front. Some drivers solve this problem by adding weight to the back and deploying snow tires to provide traction, but the fact is that pickups are not excellent choices to drive in snow across the board.

That distinction belongs to 4WD-enabled vehicles, not just pickups; 4WD distributes power to all four wheels, which translates to better grip in slippery conditions. Perhaps there's some associativity between 4WD and pickups, which is why the myth has persisted for so long. Nonetheless, the blanket statement is false.

Myth: Red cars are more expensive to insure

Several factors influence insurance rates, including car type, age, and credit history. For the longest time, drivers in America have been convinced that the color red is one of these rate deciders. It's unclear how this myth was born — perhaps there's a subconscious correlation between red cars and reckless or aggressive driving habits.

However, data doesn't back this bias up; white cars are more likely to be ticketed by law enforcement. In terms of theft, flamboyantly colored vehicles are safer than neutral colors, so it's not as if red cars are at an elevated risk of being stolen.

Truthfully, car color does not feature in insurance premiums. According to Bankrate, most insurers don't even ask about your car's color. However, while base color may not be relevant, custom paintwork might influence insurance rates. Custom paint jobs may qualify as custom parts or equipment, which translates to additional coverage. That's the extent of the deterministic power of car color regarding insurance rates.

Myth: You need AWD to drive in the snow

Another popular winter tale in the driving scene is that AWD technology is required to navigate the roads. How else are you supposed to grip the slippery surface if you're not putting all your tires to work? Well, you wouldn't be wrong for thinking along these lines, but there's a limit to AWD's usefulness — it can even instill you with a false sense of security.

AWD does help you move; its biggest selling point is its grip. It delivers power evenly through the tires to the ground to get you out of sticky situations. It'll get you moving alright, but it doesn't aid in braking or steering. There's only so much grip your tires can use, and if you get overconfident when driving with it, your front tires could lose traction and understeer.

Snow tires do the job of providing grip just as well with the extra coverage of braking and steering responsibilities, so you don't necessarily need AWD to drive around in the snow. In very slick situations that require a lot of traction, like climbing uphill, AWD does make your life easier. However, it's not AWD-or-bust as some marketing campaigns would have you believe.

Myth: You don't need an oil change if you top off regularly

As mentioned earlier in the 3,000-mile myth, changing your oil is critically important for your car's engine health. However, another school of thought in car maintenance has oil change as its centerpiece — regular additions of oil to the existing lubricant somehow replace the need for a holistic change.

Maintenance can be an expensive affair, and doubtless this myth was born as a clever solution to save some dollars. However, that penny-pinching ideology will only come back to haunt you if you subscribe to this mindset. The purpose of oil is to cool down the engine and lubricate it. Over time, oil gets dirty as it runs through the engine, changing from a semi-opaque profile to a thick black sludge.

Topping it off may increase the levels, but that doesn't make the existing oil any less dirty, which over time can lead to problems with the engine. It's fine to top off if your levels are low, but that's no substitute for actually changing out your oil.

Myth: It's okay to wait till you're low on gas to refill

One common misconception in driving maintenance culture is that it's somehow cheaper or more practical to run low on gas before refilling your tank. In theory, this might appear logical — gas mileage improves as your tank empties.

The reality is markedly different. Several factors affect gas consumption to the point where tank weight becomes negligible, and there's the added risk of malfunctions if you repeatedly run low on fuel. Modern cars use electric fuel pumps to get gasoline from the tank to the engine. These work best (and last longer) when kept cool and immersed in fuel.

When your tank is running low, the fuel pump is exposed, and efficiency reduces, which increases wear. That's not the only risk; debris can gather at the bottom of the tank due to repeated exposure, which can cause serious damage to the fuel system. Also, you could get stranded in the middle of nowhere because you're trying to save a few pennies. It isn't worth it — fill up that tank as early as possible. If you're looking for better ways to use less gas, we've got you covered. 

Myth: It's not necessary to rotate your tires

Tire rotation is one component of the maintenance calendar that can easily get overlooked; changing flats, pumping those losing pressure, and complete replacement are more in your face. So, if you're regularly changing your tires, especially if you replace all four at the same time, you may not see the point in rotating them.

That's a wrong idea. Tires wear differently depending on the type of drivetrain your car uses and its location. For instance, in FWDs, front tires wear more quickly than those at the back because they perform two duties: steering the car and delivering power to the road. Under tire rotation principles, for even wear distribution, you should swap the front and rear tires. That's not all; you should swap the position as well. That is, right rear tire to front left, and left rear to front right.

The specifics of the rotation differ among manufacturers, but the point remains that rotating tires reduces the risk of handling problems.

Myth: It's best to refuel your car in the morning

You may have heard of a relationship between temperature and gasoline — it expands when heated. Following this train of thought, if you were to buy gas in the mornings when the environment is cool, you could technically get more fuel when the sun comes out in full force due to expansion.

Unfortunately, there's little to no difference in the real world. This is because gasoline is stored underground at filling stations — away from the glare of sunlight. The result is a near-constant gasoline temperature at any point in time. So, there's actually a negligible difference in the quantity of fuel you get, whether you visit the pump at night or at noon with the sun at its apex.

You could theoretically save a few cents by adapting your refueling schedule to fit cooler temperatures, though. A study from Consumer Reports found that a 15-degree-Fahrenheit difference in temperatures would give you a gain of about 1%. However, in the grand scheme of things, this myth holds no water.

Myth: The best used cars have the lowest mileage

When purchasing a pre-owned car, one of the most important descriptive features buyers consider is mileage. The logic behind this is simple: the more miles a car puts on, the more wear and tear its parts endure. Car age also plays a role, of course, but buyers are more likely to look for lightly used vehicles.

Where this conventional wisdom starts to lose its strength is in context. A car may have, say, fewer than 20,000 miles on its odometer. However, if those miles aren't proportional to the normal usage for the number of years it has been owned, that's a red flag to note.

Just as buyers typically steer clear of overused vehicles, underutilized cars should come under the same degree of scrutiny — especially if their engines are diesel-powered. Low-mileage diesel-powered vehicles that mainly made short trips may have issues with the diesel particulate filter, something buyers should avoid.