Myths spread like wildfire, and they’re mistaken for truth before you know it. Car maintenance is no exception—what seems like good advice can harm your vehicle over time. Here are the common car maintenance myths mechanics advise car owners to ignore.

Washing Your Car With Dish Soap Is Okay

Some car owners use dish soap for convenience. However, it strips away essential wax and damages paint faster, exposing your car to environmental damage. In addition, it lacks the specific rinsing agents found in car wash soaps. For the best results, use a car-specific shampoo and a soft microfiber mitt.  

You Can Use Non-Brand Replacement Parts

OEM isn’t a fancy acronym; it stands for original equipment manufacturer. OEM parts are high-quality, more reliable, and produced with quality control. Using cheap, non-brand options may save money initially, but they lead to poor performance, premature failures, and potential vehicle damage.  

Overinflate Tires for Better Gas Mileage

This tip might sound like a clever hack to save fuel, but it can backfire. The trade-offs include reduced tire grip, uneven wear, and a bumpier ride, which aren’t worth it. Plus, overinflated tires blow out faster. You’re better off sticking to the manufacturer’s recommended pressure.  

Check Tire Pressure Only When it Looks Low

We often rely on our eyes and visual cues to check tire pressure because it’s easier. However, this half-hearted effort leads to under-inflation, poor fuel efficiency, uneven tire wear, and reduced safety. Tires can be low even if they don’t look it. The ideal approach is to check tire pressure monthly.

It’s Okay to Replace a Single Tire Instead of a Full Set

Installing just one tire instead of a full set causes uneven wear, poor handling, reduced traction, and imbalanced driving. This mismatch strains the vehicle’s drivetrain and may lead to costly repairs. If you can’t replace all four tires, ensure the new one matches the others. 

You Can Use Any Type of Oil

Carmakers design engines to run on different types and grades of oil, so lubricants have varying viscosities and additives. Although using anyone you can find might seem convenient, it can harm your engine. It would be best to use only the oil type recommended in the owner’s manual.

Water Can Replace Coolant

Water is a bad replacement for coolant because it lacks the essential additives that prevent corrosion, freezing, or overheating. Don’t try to cut costs with water because it is readily available; it doesn’t pay off in the long haul.  

It’s Okay to Mix Different Coolants

When you combine coolants with varying chemical compositions, it can cause clumping, corrosion, and even system failure. Each coolant type has specific properties designed for particular engines. Rather than relying on quick fixes, always use the recommended coolant type and follow manufacturer guidelines.  

Fuel Type Doesn’t Always Matter

Adding premium fuel to a regular engine is a misguided tip without benefits—just an expensive bill. However, using regular fuel in an engine designed for premium would cause knocking and gradual damage. Why? Some engines operate at higher compression ratios and need higher octane fuel (premium) for optimal performance.  

Flushing the Transmission Fluid Shouldn’t Be Often

Transmission fluid lubricates car parts, helps cool gears, and improves hydraulic power. However, it gathers metal particles and debris over time, causing premature wear. The best tip is to follow your car’s maintenance schedule for flushing, usually every 30,000 to 60,000 miles.  

Keep Topping Off the Gas Tank

While you may want to squeeze in extra miles, constantly topping your fuel tank can damage your car’s vapor recovery system. It can also result in fuel overflow, paint damage, and unnecessary spending. Stop when the pump clicks off the first time to prevent costly repairs.

You Can Always Maintain Your Car With DIY Repairs

DIY may sound like a money-saver, but you should leave complex repairs to the professionals. Know your limitations and stay away from complicated fixes. For instance, misplacing cables or incorrect handling can short-circuit electronics or damage the battery. 

Some Leaks Are Minor

Leaks often come from worn seals, gaskets, or hoses. While small pools might seem insignificant, they indicate underlying issues that can worsen over time. Your car may be at risk of overheating, brake failure, or engine damage, and you will only know if you visit a mechanic.  

Replacing the Timing Belt Isn’t Very Important

The timing belt keeps your engine’s valves and pistons moving in sync. If it breaks, it may cause major engine damage, costing thousands. Manufacturers recommend that car owners replace it every 60,000-100,000 miles. 

You Should Rev the Engine Before Turning Off the Car

Although many car owners believe constant revving clears out the engine, it is not entirely true. The right time to rev is when warming up a classic car or testing engine performance—do it gently and only when necessary. Constant revving wears out your engine components, increases carbon buildup, and wastes fuel.