Do You Know What's Bad for Your Car, and What's Not?


By: Staff

7 Min Quiz

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About This Quiz

How well do you know what your car needs to run properly? Take this quiz, and rate your knowledge!

How many miles do you go before getting an oil change? Three thousand? Five thousand? Ten thousand? More? In all honesty, most cars do not need to have an oil change every three thousand miles, regardless of what that drive-through oil change sticker says. The majority of today's vehicles need an oil change roughly every five thousand miles, according to most major auto manufacturer manuals. However, although you may be tempted to push it, don't go ten thousand miles without an oil change. Although, some "experts" are now saying that an oil change every ten thousand miles is not likely to do any damage unless you do a lot of stop and start driving, is that a chance you want to take?

Regularly servicing your car's fluids is one of the easiest, cheapest, and least time consuming of all vehicle maintenance tasks, yet one of the most important to stay on top of. Don't risk your car's engine or transmission by slacking off on your fluid changes and top-offs.

Even if you're not a mechanic, you should be able to describe basic auto service requirements for your car. Take this quiz to find out how much you know!

What can become damaged if you don't check your car's brake pads for wear?

Failing to check the brake pads for wear can lead to bigger and more expensive repairs later on, including the brake drums or rotors.


When you're shifting a manual transmission, it may feel natural to leave one hand on the lever. Why shouldn't you?

Using the shifter as a hand rest is frowned upon for a few reasons. Let's talk safety, first. With only one hand on the steering wheel, you're not able to make sudden steering corrections or maneuvers, if needed. And then there's what it does to your vehicle. Your resting weight on the lever strains parts of your car's transmission, including the bushings and synchronizers, and leads to general premature wear on the gear teeth.


What is the result of not replacing your car's battery every five years?

You can expect most car batteries to last about five years. Beyond that, the acid of the old battery may do some damage, including corroding the battery terminals and the cables that connect with the battery posts, as well as damaging the strap holding the battery in place.


Which type of tire is good for general use, and typically lasts longer than others?

For the longest-lasting, all-around good general tire, consider all-seasons. Consumer Reports testing has found the best all-seasons can last for almost 100,000 miles, while the worst can need replacing after 55,000 miles.


What's the best motor oil to use?

Using the wrong oil may not seem like a big deal. Engine oil lubricates, so any oil is good, right? Not exactly. While it's true a lubricated engine is a well-running engine, using the wrong oil viscosity (its thickness) is a big deal. It may not lubricate as well as it should, which can shorten the life of your car's engine. Stick with the viscosity recommended by your car's manufacturer, found in the owner's manual.


What could happen if you carry a lot of heavy gear in your car?

The heavier your vehicle is, the more stress it puts on parts such as the brakes, drivetrain and suspension. And more weight also means it'll use more fuel. Additionally, carrying too much weight on your car may affect its braking, handling, stability, towing capacity and rollover resistance. In extreme cases, you could damage the transmission -- especially going uphill -- damage the suspension, cause structural damage or even blow the tires.


Which is not true about sudden stops?

Sudden stops, and quick acceleration, can cause a few problems. Not only will it cause your gas mileage to take a nosedive, it can also cause wear on parts including brake pads and rotors. Both habits can damage drivetrain components like engine and transmission mounts, as well.


It's OK to let which symptom slide for awhile?

You hear an occasional knock or an intermittent squeak or feel an odd new vibration. It could be superficial, and therefore no big deal, but it could be an early warning sign that something is going wrong. Neglecting minor symptoms can mean big bills -- and maybe a tow truck -- later.


What would happen if you put jet fuel in your SUV?

This is a true story, actually. A fuel delivery service accidentally filled a pump with jet fuel at a gas station in New Jersey. The cars that had filled up on the kerosene didn't perform better. In fact, because auto engines can't combust (burn) this fuel, they all stalled.


It's OK to skip oil changes, right?

Skipping them, or just not doing any (yikes!), will at first cause your car's engine to run less efficiently, but over time that's not all. Without proper lubrication, the components of your car's engine will warp and wear out, leading to catastrophic failure. The concept of doing an oil change every three months or 3,000 miles is a bit outdated, but your car does need to have regular oil changes. For many modern cars the interval is often every 5,000 miles, but you'll need to read your car's owner's manual for its recommended interval (and type of oil).


Your car's owner's manual recommends using 87 grade gasoline (Regular) in your car. Would 89 (Plus) or 92 (Premium) be even better?

If 87 Regular is suitable for your vehicle, there's no need to fill up with Plus or Premium grades in an effort to give it a treat. Octane ratings don't work that way. The ratings measure how well the fuel mixture can withstand pre-ignition knocking -- high-performance engines will perform better with higher octane.


It's no surprise you brake to slow your car down when going downhill -- after all, that's one reason for having brakes. But why is riding the brakes bad?

Riding your brakes, whether it's downhill or as a bad habit, can cause excessive wear and tear on your car's brake pads and rotors, causing them to warp. Remember, too, the decompression that's occuring in the car's drivetrain will help keep your car's speed in check. Instead of riding your brakes to keep your car from going too fast, try shifting into a lower gear.


Driving with unbalanced tires can cause what problem?

For the smoothest ride, best traction and steering control, and least wear and tear on your tires, it's important to have your tires balanced. Unbalanced tires can cause poor gas mileage and rough vibrations that you feel in the cabin. Plus, in addition to putting unnecessary stress on the car's bearings, shocks, and wheel assembly, you'll see uneven wear on your car's tires.


Which is a symptom of a dirty air filter?

A lot of car owners admit they skip oil changes. But what about changing your car's intake air filter? We don't mean the one that filters the cabin air. We mean the one that filters the air before it enters your car's engine. It's important because the dirtier the filter is, the more it can restrict air flow to the engine, which, at first robs the engine of power, and then eventually causes the engine to overheat. Maintenance schedules vary depending on the car, so check the owner's manual for the recommended interval for your car.


How often should you change your car's coolant?

Although you can expect many modern coolants to last for 5 years or 50,000 miles, most experts stand by just one rule here: if you take the cap off your car's radiator, peek in and see that the coolant looks dirty and brown, it's time for a change. Depending on your car and on driving conditions, that could be every two years, as some mechanics recommend.


How often should you check your vehicle's tire pressure?

Did you know that the pressure in your tires is reduced by one pound per square inch (PSI) for every 10-degree drop in the air temperature? And they also lose up to one PSI every month, so it's good to check them about every 30 days. It'll help not only the handling, but also your gas mileage. You'll know your tires are properly inflated if they each match the PSI found on the sticker inside the driver’s door of the vehicle (or in the owner's manual).


If you drive a manual, you know if you forget the parking brake the car will roll away. But do you need to use the parking brake if you drive an automatic?

The parking brake may not seem like it does much -- after all, the car's in 'Park' -- but when it's engaged, it will hold your car in place better than 'Park' alone. Not using it in a car with an automatic transmission does make a difference, and can take years off the life of your transmission's components. And, it is also true that without regular use, the cables for the parking brake, which are under the car, can corrode or break.


How long should you let your car warm up before you drive away?

This is one of those things where some people argue it's best to warm a car up -- which means you're bringing the engine and all the fluids up to temperature -- before driving it, and others believe it's no longer necessary in new cars. However, there's no need to let it idle for awhile. Give it about 30 seconds to loosen up before you go.


Why shouldn't you top off your gas tank after the pump has shut off?

Topping off your fuel tank may seem like no big deal -- hey, more fuel! But, it can actually cause your car to run poorly, it may even damage the engine, and it's definitely not good for the environment. Additionally, modern fuel pumps have vapor-recovery systems, which don't allow extra fuel to go into your tank. That extra gas you think you're getting is actually fed right back into the gas station's tanks, although you're paying for the top off.


Why is it bad to keep your car in a heated garage in the wintertime?

While your car's engine doesn't mind a warm garage in the cold winter weather, the exterior of your car begs to differ. A car that's been out in the elements -- snow, ice, and the chemicals used to treat the wintery roads -- and is kept in a heated space has an increased risk of developing exterior rust. Parking in a garage or covered space is fine, just make it one that's not temperature-controlled.


You're driving down the street and encounter a "Caution: High Water" sign. Do you drive across?

An engine's cylinder contains air and fuel. Air is compressible, so when the piston squeezes it, the pressure goes up. Water, however, is not compressible, and if it's in your engine's cylinders when the piston tries to squeeze, things break -- known as a hydrolocked engine. It can happen, for some cars, in just a few inches of water.


What's the best type of weather to wash your car?

Hot, sunny days may seem ideal for a car wash, but when the water and soap meet the heat of your car's exterior you won't be able to keep up with how fast the droplets dry -- and that means residue. This soapy, grimy residue doesn't just give your car a dull appearance, it also leaves it at risk for paint damage. For the spotless finish you're looking for, a party cloudy or overcast day between 60 and 80 degrees Farhienent is ideal for washing and waxing your car. And if it's always hot and sunny, move into the shade before you begin, or wash and wax early in the morning or in the evening.


What's the best way to defrost an icy windshield?

Never, ever, pour hot water on an icy windshield, unless you're in the market for a new windshield. the hot water will shatter an ice-cold windshield. The best way to remove snow and ice from your car's windshield is with its defroster, on full blast, and an ice scraper with a little elbow grease. Spraying a mixture that's two parts 70 percent isopropyl alcohol and one part water will also do the trick.


Is it true the best way to clean your car's engine is to pressure wash it?

Pressure washing your car's engine will get it clean, that's for sure -- but it may not run afterward. The preferred way to clean an engine used to be to steam clean it, but today's safe cleaning includes a degreaser and a regular ol' garden hose. Both are improvements over shooting jets of water in and around all those seals and hoses and electrical parts.


Each of these is a reason to service your car under the "severe" maintenance schedule, except which one?

A 2009 study by AAA found more than 50 percent of all motorists are following the wrong maintenance schedule. If you tend to drive in hot or freezing (extreme) temperatures, if you drive in stop-and-go traffic or at speeds less than 50 mph for long distances or if you tow a trailer or use your car's roof rack you should be following the "severe" schedule. Also considered severe? Frequent driving on roads that are dusty, muddy or spread with loose gravel, driving in mountainous areas and extensive braking.


Why is it bad to skimp on or skip the car wash?

Did you know dirt can hurt your ride? It can wear down your car's paint job, and when your car's paint gets compromised it sets the stage for rust. And rust is the flesh-eating bacteria of vehicles. Some experts will say a weekly wash is best. If that seems like a lot, just try to keep it clean. And don't forget to wax. It adds a protective barrier between the paint and the world.


What indicator light in the instrument panel of your car lights up when there's a problem in your car's computerized engine-management system?

Whether you call it the malfunction indicator lamp, the check engine light or the service-engine-soon light, when it comes on, don't ignore it. It could be minor like a loose gas cap or a major engine problem, but you won't know until you take it to a mechanic. When it illuminates it indicates there's a problem with your car's computerized engine-management system. The longer you wait to get that check engine light checked, the more likely you are to cause serious damage to your car.


Shifting from reverse into drive without coming to a complete stop before switching can cause damage to what part of your car?

Shifting suddenly from reverse into drive without stopping between isn't going to cause your engine to seize or your transmission to fail today. But continue this driving habit over time and you'll do damage to your car's drivetrain: that's the transmission, differential and drive shafts.


How will you know if your car's air conditioning system is on the fritz?

In order for your car's air conditioning to work properly, it needs a refrigerant. Over time, that refrigerant can leak through the seals, but you won't know it's happening until the day you notice the air conditioning system isn't blowing cold air through the vents. To restore it, the unit needs a recharge. And while refrigerant leaks are common, the AC may also fail from a fan not working or a faulty compressor.


Your car needs periodic preventive maintenance. How often should you bring it in for a tune-up?

Generic tune-ups aren't really needed on modern cars with on-board computers. However, following the suggested preventative maintenance for your car -- look in your car's owner's manual for its schedule -- is always recommended.


Are oil additives good for your car?

It sounds like a good idea -- your car's engine is getting old and tired and an oil additive will rejuvenate it. Except it won't, and the Federal Trade Commission has targeted companies selling the products for false advertising claims.


When you're driving a manual and you're stopped, should you keep the clutch pushed to the floor?

It's convenient to keep the clutch engaged when you're stopped -- you can quickly inch forward in stop-and-go traffic, or take off at a green light. However, your car likely thinks it's inconvenient. Keeping it engaged this way can cause premature wear, and it can also damage parts of the clutch system, like the release arm or the pressure plate. Better to keep it in neutral with the clutch out until it's time to go.


Which is not a sign your car is out of alignment?

It's normal wear and tear on your car's suspension and can happen as easily as when you bump a curb while parking. You'll notice your car pulls to the left or right while you're driving. Or you may notice the steering wheel vibrates, or it's crooked although you're driving straight. And, in addition to these, when your car is out of alignment the tires will, also, wear unevenly. Having your car aligned when you see these signs can save you money on tires and gas, and will also keep your ride safer.


What can happen if you routinely keep your car's fuel level low?

It may seem pretty harmless, but adding only a few gallons of gas at a time or regularly running with your tank a quarter full or less can damage your car. There are two common problems that can happen when you do this. One, there isn't enough fuel in the tank to keep the fuel pump submerged, and many pumps rely on that to keep from getting too hot. And, two, gunk. If the fuel level isn't very high, it forces the system to pump gas from the bottom of the tank -- and that's where sediment naturally builds up. That sediment can clog your car's fuel filter, and it can damage the engine.


Sure, it's fun to open it up for no reason other than to enjoy the speed. Other than the obvious safety concerns, why is it bad for the car?

Hard acceleration, and the hard braking that follows, is hard on your car's drivetrain and on its braking components. Safety aside, indulging in this can add a lot of extra wear and a lot of additional repairs.


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