Can You Identify These Common Auto Maintenance Mistakes?

Justin Cupler

When rotating tires, you should always…

The only way to ensure your wheels are as tight as needed without stretching the wheel studs or weakening them is to torque the lug nuts to the manufacturer's recommended setting.

You must change your oil every 3,000 miles.

The 3,000-mile oil-change interval was a product of the quick-lube industry to get you to visit their shops regularly. Each manufacturer has its own recommendation for oil-change intervals that generally fall between every 5,000 and 10,000 miles.

What type of engine coolant should you use?

The coolant in your engine is just as important as any other fluid, as it not only cools the engine but also lubricates the cooling system components and helps prevent freezing in cold weather. Using the manufacturer-recommended coolant -- you can find what the manufacturer recommends in your owner's manual or online -- keeps this system in top shape.

When should you change the belts on your engine?

The rubber surrounding the cords that make up your engine's belts breaks down slowly, and its first signs of excessive wear are small cracks on the grooved side of the belt. This is an indicator it's time to replace them.

When do I know my tire tread is dangerously low?

Most tires have built-in wear indicators in the form of rubber bars in the valleys between the tread. When the tread is even with these bars, the tires have lost their ability to effectively cut through water and maintain maximum traction.

What can happen when you only replace brake pads?

Your brake system requires multiple items to work at peak performance to maximize braking longevity and efficiency. Replacing just the pads and ignoring the condition of the rotors and calipers can result in premature pad wear, brake noise, or even brake failure.

When should you replace the radiator hoses on your car?

Radiator hoses wear out slowly from constant heating and cooling. Eventually, the semi-hard rubber loses its rigidity, which can allow them to expand and potentially burst while driving. If the hoses collapse under light pressure from your hands, it's time to replace them.

Spark plugs come pregapped, so I don’t need to check them, right?

Though spark plug manufacturers pregap their plugs, they can fall outside specifications from an impact during shipping or any other outside force. Because we are dealing with tolerances within thousandths of an inch, you always want to check and adjust spark plug gaps before installing them.

What is the best soap for washing a car?

Automotive soap manufacturers specially formulate their soaps to remove dirt and grime without damaging your vehicle's paint. All other soaps have mild abrasives to help them clean better, and these can cause scuffs and scratches in your vehicle's paint.

What oil weight should you use in your car?

Everything inside your engine has been tuned to perfection, and engineers spend countless hours determining the right engine oil to maximize lubrication, fuel economy and performance. Straying from the recommendations in your vehicle's owner's manual can reduce fuel economy, lower lubrication effectiveness or reduce performance.

How often should you change your spark plugs?

Spark plug life varies greatly between manufacturers and engines, as it's based mostly on tolerances of the engine and the type of spark plugs they use. With most cars now using platinum spark plugs and running cleaner than ever, many have 100,000-mile spark plug intervals. That said, always refer to the owner's manual to see exactly what the manufacturer recommends

What pressure should I set my tires to?

Manufacturers engineer vehicles to operate within a range of settings, including tire pressure. Inside the door you will find a placard that lists a "Cold PSI" setting. This is the temperature your car's tires should be at before driving. Anything more or less can negatively affect fuel economy or ride.

Why do you need to change brake fluid?

Brake fluid is hygroscopic, which means it absorbs water from the atmosphere. This fluid is designed to prevent boiling even at extremely high temperatures, and water lowers this resistance to boiling. If brake fluid boils, it can damage brake seals and introduce air into the system.

Can I toss out used oil wherever I want?

Used oil is highly toxic and damaging to the environment. There are recycling centers that refine this oil and convert it into other useful chemicals. Many auto parts stores will take your old oil to these centers for you.

How do you properly perform the final engine oil level check after changing the oil?

Starting the engine allows the oil to cycle through the filter and the engine. Checking the oil after running the engine verifies there is plenty of oil left in the pan after the oil filter sucks some into it. Failure to check this way could result in a low oil level and cause engine damage.

What should you always do before screwing on an oil filter?

The rubber seal on the oil filter keeps oil from spilling out when driving. Always remove any debris from the seal and apply a thin coat of oil to it before tightening the filter to prevent the seal from bunching and leaking.

You should refill the radiator fluid when it’s hot, right?

The cooling system operates under pressure to prevent boiling. If you remove the pressurized filler cap while the engine is hot, the fluid can immediately boil and shot out of the radiator reservoir. This hot fluid can contact you and cause severe burning.

Where do you refill the oil?

Every engine has a large oil-filler hole on top of the engine, and this is where you fill the oil. Always use a funnel, though, as spilling oil on the engine can cause smoke as the engine warms up.

Cars don’t really need transmission fluid exchanges, right?

Transmission fluid has many jobs. It acts as a hydraulic fluid, a lubricant, a coolant and a cleaner. Over time, this fluid gets dirty and loses its effectiveness. Most manufacturers set a specific schedule for changing this fluid to prevent damage.

You can throw out those little packets of grease that come with brake pads, right?

Some brake manufacturers put grease in with their brake pads, and they do this for a reason. This grease lubricates the brake caliper slides, preventing the calipers from sticking and causing excessive pad wear. If the pads have this grease included, make good use of it.

Should the oil drain plug be as tight as I can get it?

Torquing the drain plug to its proper tightness ensures it seals completely against the pan to prevent leaks. It also saves you from the stress of accidentally stripping the oil pan.

When will you get the most accurate tire pressure reading?

As you drive, the tires warm up and pressure inside them rises. You should always check tire pressure when they are cold for the most accurate readings. You should also fill the tires when they are cold.

Should I use a pair of channel-lock pliers to remove my oil filter?

There are hundreds of oil-filter tools that remove various filters without causing damage. Using channel-lock or slip-joint pliers can result in you crushing the filter and pieces of the filter contaminating the oil system.

When do you know your brakes need replacing?

Waiting until your brakes squeal or grind may be too late, as this means there is potential damage already being done. You should inspect your brake pads when rotating your tires and replacing them when there is less than 1/8-inch of pad material left.

Using a power ratchet on spark plugs is a great way to save time, right?

Spark plugs have ceramic caps that break easily, Using a power tool can snap them off during installation. This can also result in you stripping the threads in the engine and causing expensive damage. Hand-tighten the spark plugs and tighten them only to the manufacturer's recommended torque.

Does using premium fuel make my car run better?

Manufacturers design vehicles to run on certain types of gas, and most run on regular unleaded fuel (AKA 87 octane). Cars designed to run on regular gas will see no improvement by switching to a higher octane as this fuel simply resists preignition in the engine. The only time you will notice a difference is if you drive a vehicle that has different output ratings for the different fuel types, which is rare. Always defer to the manufacturer's recommended fuel for maximum performance and savings.

There is no need to mix my coolant. Just straight water works.

Water is fine to get you home in a pinch, but running only water all the time will cause rusting within the cooling system. It also can freeze in cooler climates, causing major internal engine problems.

How often should you have your tires balanced?

Tires are naturally out of balance -- it's just how they are built. Tire installers use small weights to offset the heavier parts of the tire. As the tire wears, these heavy spots can move, and rotating the tires can expose an out-of-balance issue you never noticed before. Save yourself the stress and your tires the excessive shaking and balance them while having them rotated.

The most important early-spring maintenance item in cooler climates is…

Salt causes rust, and in cooler climates, you'll encounter a lot of this on the road in the winter. The most important maintenance item after a long winter is to have the undercarriage pressure washed to clear off all that rust-causing salt.

How often should you rotate your tires?

Tire rotation is less of an exact science than other maintenance items on your vehicle. Most manufacturers and experts recommend rotating the tires every other oil change to keep tire wear even.

How often should I have my vehicle’s alignment checked?

Our roads are tough on our cars, and they are especially tough on alignments. Because of this, it is best to have a professional check your vehicle's alignment every six months. Most shops will handle the check for free. Keeping your alignment within specification will help reduce tire wear and save you cash in the long run.

How often should you wax your vehicle?

Waxes differ in chemical compound, making some last longer than others. In general, you'll want to refer to the instructions on the wax to determine how often to reapply the wax. Applying too much wax can cause a buildup and lead to paint damage.

My oil is black right after an oil change. Is this an issue?

When you change your engine oil, you cannot remove all the old, black oil. When you start the engine, this old oil mixes with the new oil, making it look darker. This is no issue at all.

Once you use synthetic oil, can you go back to conventional?

There was a massive old mechanics tale that claimed switching from synthetic oil to conventional oil would cause engine issues. The stories range from congealing oil to leaks to immediate engine failure, but none of them are true. Synthetic oil is still just oil, but engineers have synthetically modified it to provide better flow rates and lubrication. Mixing them will cause no issues -- they even sell these mixed oils in stores.

Should I get a fluid change to fix my slipping transmission?

Once a transmission starts slipping, there is already internal damage, Forcing new, clean fluid into the system can exasperate the issue. It is best to let a professional repair the transmission and start fresh with regular maintenance.

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About This Quiz

Spending a little money now in maintenance can keep your vehicle running in top shape for as long as possible, which spares you from big repair expenses down the road. Things like changing your oil, rotating tires, having regular regular alignments performed and even changing your car's brake fluid can all play a role in saving you money in the long run.  That oil change you skip now can cost you 10 times as much down the road.

The problem with maintenance is not many car owners are automotive experts, and this lack of expertise can lead to big-time mistakes that can cause damage or waste precious dollars. Understanding what's right and wrong when maintaining your vehicle can save you cash now and keep you from causing more damage than good. Things like overtightening bolts, missing important steps and simply not adding the right fluids can all cause money-draining damage to your vehicle. Fortunately, these issues are all avoidable with a little research and some automotive know-how. 

Do you think you've got the automotive knowledge to identify the common car maintenance mistakes most amateurs encounter? Take this quiz to find out if you can identify common maintenance mistakes. 

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