Common car maintenance services and repairs explained
How do you know if you car really needs the services that your dealership or repair shop recommends? What if the suggested service is not included in the maintenance schedule? Let's look at the common maintenance services first:
Tip: always ask what exactly is included in this or that "service"
Fouled spark plug.
A tune-up is a major service that combines an oil change, replacing spark plugs and possibly a few other items depending on your vehicle's mileage and maintenance requirements. How do you know if your car needs a tune-up? A tune-up is usually done whenever your spark plugs are due, or if your engine isn't running as smooth as before. A tune-up is a good way to start, if you have difficulty starting, or if your engine runs rough occasionally, or if your gas mileage is getting worse. However, a tune-up is more of a preventative maintenance for your engine than a universal solution for all problems. Read more: How often does a car need a tune-up
Drive Belt Replacement.
If you have a car with a gasoline or diesel engine, it has at least one drive belt that drives mechanical accessories attached to the engine, such as an alternator, water pump, power steering pump and an air conditioner compressor. Some cars have two or three belts. With mileage, a drive belt wears out and eventually can break if not changed in time. How often should it be replaced? Are there any signs that the belt is getting bad? Read more »
Air Filter Replacement.
Engine air filter: dirty versus clean.
An engine air filter protects your engine. Without an air filter, your engine would wear faster, as the sand particles would scratch cylinder walls. Over time, the filter clogs up. A clogged-up air filter restricts the air flow and reduces engine power. Normally, a mechanic checks the condition of an air filter during the oil change. Replacing an air filter is not very difficult. What are the symptoms of a dirty engine air filter? How often should it be replaced? Read more »
Coolant Change (Flush).
Topping up coolant.
Modern cars have a liquid cooling system that prevents an engine from overheating. It's filled with coolant (antifreeze). The coolant change (flush) is another service that many dealers and repair shops often recommend. When does the coolant need to be changed? We suggest checking the maintenance schedule. Modern cars use a long-life coolant. For example, the maintenance schedule for the 2014 Toyota Camry recommends checking the coolant regularly and changing it at 100,000 miles. Changing it earlier doesn't make much sense unless there is some problem with the cooling system or quality of the coolant. It's also important to use only the recommended coolant type.
Transmission Fluid Change (Service).
Changing transmission fluid.
In many modern cars, the transmission fluid change is not even mentioned in the maintenance schedule, or included only for severe driving conditions. Does that mean it's filled for life? We know that the transmission fluid deteriorates over time and transmission repairs are expensive.
When should you change it? Why is it risky to change transmission fluid in high-mileage cars? Is a drain-and-refill method safer? How do mechanics check the fluid level and condition if there is no dipstick? Read more: »
Power Steering Flush.
Power steering fluid.
While most of the cars today come with electric power steering (EPS) that has no fluid, some cars and trucks still have a hydraulic power steering. In a hydraulic power steering, the system is filled with a special fluid that transfers hydraulic pressure and lubricates the internal parts. As the parts wear, the fluid becomes contaminated with metal and rubber particles. When should the fluid be changed? Many car manufacturers don't include power steering fluid change into the maintenance schedule, but rather advise checking the fluid regularly. We know keeping the fluid clean will help reduce the wear. So, if it's not in the maintenance schedule, the key question is how dirty is it? The condition of the fluid can be checked in the power steering fluid reservoir under the hood. Changing it only makes sense at higher mileage, if the fluid is dirty. Of course, it's important to use only the specified fluid type and maintain the proper level.
Front/Rear Differential Fluid Change (Service).
Rear Differential, Ford Mustang.
Rear-wheel drive and all-wheel drive cars and SUVs have a rear differential. 4WD trucks have front and rear differentials. A differential is filled with a special fluid (gear oil) that needs to be changed in recommended intervals. The differential fluid needs to be changed more often if you use your vehicle for off-roading, towing or like to drive fast. The good news is that this service is not very expensive. Many dealers offers what they call 4x4 Driveline Service that typically includes fluid change in front and rear differentials as well as in the transfer case. Read more: How often should gear oil be changed?
Transfer Case Fluid Change (Service).
Transfer case. Dodge RAM
What is a transfer case? A transfer case is a part of an AWD or 4WD system. In 4WD trucks, it's a large device attached to the transmission (in the photo). It may contain a central differential, low-range gearing and other controls of the 4WD system. Small and medium all-wheel drive SUVs have a compact transfer case or unit. A transfer case fluid need to be changed in recommended intervals. How often? A lot depends on the use of the vehicle. Read more: When transfer case oil should be changed?
At 80K miles, this engine is clean inside thanks only to regular oil changes.
What is an engine flush? It's flushing the inside of the engine during an oil change with a chemical designed to dissolve carbon deposits (sludge). Some shops use an engine flush machine, others simply add an additive into the engine and run it for a few minutes before changing oil.
There are cases when an engine flush can help, but it also can cause some problems. For example, if an engine is badly sludged up inside, loose deposits can block the oil pickup screen and restrict the oil flow after the flush. If you change oil regularly in your car, an engine flush is not necessary. Car manufacturers, in general, also don't recommend flushing the engine. Plus, many modern cars use synthetic oil that doesn't leave as much deposits as mineral oil.
Fuel Injector Flush (Fuel Injection Service).
A fuel injector flush is commonly recommended for older high-mileage cars that have some issues with the engine performance. What is a fuel injection flush? A mechanic runs a special cleaner solution through the fuel injection system to clean the fuel injectors and de-carbonize the engine combustion chambers. Yes, the fuel injection flush can make a high-mileage engine run smoother, but it won't be much of a benefit if the engine runs well and there is no driveability issues. Manufacturers don't include this service in the recommended maintenance.
Tip: An automotive section of a local department store offers a variety of fuel system additives that are designed to clean fuel injectors and de-carbonize pistons. Prices range from $5 to $25.
Throttle Body Service.
Dirty throttle body.
Modern cars have a drive-by-wire system where pressing the accelerator pedal sends the signal to the computer that in turn activates the throttle valve. Over time, carbon deposits accumulate on the throttle valve and throttle body, preventing it from operating correctly. In some cars, this may cause the throttle valve to stick, resulting in low or unstable idle speed or stalling. The throttle body service involves cleaning the throttle body with a special cleaner and removing carbon deposits from the throttle valve. At what mileage should this service be done? Read More: When does a throttle body need to be serviced?
Fuel Induction Service.
Fuel Induction Service.
A fuel induction service typically includes a cleaner spray or foam used to clean the intake manifold and intake valves. This service might be helpful to a degree in a high-mileage engine with Direct Injection. In a direct injection the fuel is sprayed directly into the combustion chambers and not through the intake valves as in the conventional port fuel injection. This can cause excessive carbon build up on intake valves at higher mileage, which in turn, can result in various driveability problems, including lack of power, rough idle, hesitation and misfiring. Of course, it doesn't make much sense to do this service at low mileage. Your vehicle's maintenance schedule won't mention this service either.
Spark Plug Replacement.
Old spark plug.
Spark plugs ignite the compressed air-fuel mixture in the engine cylinders. Over time, deposits building up on the spark plugs reduce their performance. Old worn-out spark plugs can cause hesitation, misfiring and other driveability problems. Car makers recommend replacing spark plugs in regular intervals. Are there any signs that spark plugs are worn out? Can a mechanic check he condition of the spark plugs? Read More: When do spark plugs need to be replaced?
Timing Belt Replacement.
In some cars, an engine has a timing belt (in the photo) that drives the camshaft(s). It might also be called a "cam belt." With mileage, a timing belt wears out and can break. If a timing belt breaks, the engine will stall, and in some cases, might even need expensive additional repairs. Car manufacturers recommend replacing a timing belt in regular intervals. What happens if a timing belt is not replaced? Can a mechanic check the condition of a timing belt? Read more »
Battery Terminal Service.
Servicing battery terminals.
Many dealers and auto repair shops visually inspect the battery terminals during regular oil changes. If any of the battery terminals looks corroded, like in this photo, a mechanic may recommend servicing your battery terminals. The battery terminal service includes cleaning the battery posts and terminals and applying a protective spray or grease. This helps prevent various electrical problems. Of course, if the battery terminals are clean and tight, this service will not be as beneficial. Read more »
What is a tire rotation? It's when tires are moved or "rotated" between front and rear axles and, in some cases, from side to side. A tire rotation helps even up the tire wear, as front tires wear differently than the rear ones. While doing a tire rotation, your mechanic can check your brakes, as they are more accessible when tires are removed. Regular tire rotations prolong the life of your tires. Typically, car manufacturers recommend rotating tires at every oil change. Some sports cars have different tires on the front and rear axles and don't need tire rotation.
Performing the 4-wheel alignment.
The wheel alignment is a service where a mechanic checks and adjusts the angles of the wheels relative to each other and to the car body. For most cars, you won't find the wheel alignment in the maintenance schedule, but wheel angles do change over time. This happens as a result of wear of suspension components and sagging of the springs. Hitting potholes and curbs can also throw the wheels out of alignment. How often should the wheel alignment be done? Does a car need the wheel alignment after steering, or suspension repairs? What are the signs of a car needing a wheel alignment? Read the article: How often should the wheel alignment be done
Wheel balancing can help if you feel a vibration at highway speeds. To balance a wheel, a mechanic removes it from your vehicle and spins it on a computerized wheel balancer machine. If the wheel is out of balance, a mechanic attaches small weights to the rim to compensate. Of course, if there is no vibration, balancing wheels will not be as beneficial. Normally, wheels are balanced whenever tires are removed from the rims, for example, when removing a tire to patch it up or when installing new tires.
Cabin Filter Replacement.
A cabin filter is installed in the heating and air conditioning system. It cleans the air that enters the cabin.
A dirty or clogged up cabin filter can cause a bad smell and reduced air flow from the vents. Dirt on the cabin filter can promote mold, fungi, and bacteria growth on its surface. This can cause allergic reactions and other health issues. Recommended replacement intervals vary between 15,000 and 30,000 miles. Some car manufacturers recommend cleaning the cabin filter every 12-18 months. For example, for the 2010 Camry, Toyota recommends cleaning the cabin filter every 18 months or 15,000 miles and replacement every 36 months or 30,000 miles.
Tip: in many cars, a cabin filter is installed right behind the glove box and is easy to replace.
A/C Performance Service.
Measuring the temperature of the A/C air from the vents
Many dealers and repair shops offer what they call A/C Performance Service that includes recovering and refilling the air conditioning system refrigerant. Does your car need it? This service only makes sense if your A/C is still working, but is not as cold as before; over time, a small amount of the refrigerant could leak out. Of course, if your air conditioner is working fine, your money will be better spent elsewhere. The vehicle air conditioning system doesn't need any maintenance other than replacing a cabin air filter and keeping the A/C system water drain clean. If the air conditioner is not working at all, it will need to be diagnosed properly to repair.
Struts and Shock Absorber Replacement.
Struts in a car.
Struts and shock absorbers are parts of the vehicle suspension. They absorb shocks from road bumps and potholes and keep your vehicle riding smoothly. Most cars have struts in the front and shock absorbers or struts in the rear suspension. Struts and shock absorbers don't need to be replaced in regular intervals, but they do need to be inspected periodically. If a strut or shock absorber is bad, it must be replaced. Driving with a failed strut or shock absorber is unsafe. Struts and shock absorbers wear faster if roads are bad. What are the symptoms of a bad strut? Is it necessary to replace them in pairs? Read the full article: When struts and shock absorbers should be replaced?
Control arms are vital components of the front suspension. If a control arm fails, the safety of the vehicle is compromised. Replacing a control arm often requires the wheel alignment to be done to bring the steering and suspension angles back to within the specifications. How does a control arm work? Is it necessary to replace both control arms if one is bad? Read more: When do the control arms need to be replaced?
About maintenance schedules
Your vehicle's maintenance schedule lists basic regular services that your car needs and recommended mileage intervals when those services need to be done. Checking your maintenance schedule might be useful when your dealer or a repair shop suggests some additional services that "are recommended at this mileage." You can find the maintenance schedule in your car's owner's manual or in a separate brochure that came with your car. Some car manufacturers post maintenance schedules online; here are a few links:
- Find a maintenance schedule in the Warranty and Maintenance Guide that you can download in the pdf format (Follow the tab "Resources" and select "Manuals and Warranty")
Nissan Maintenance Schedules
Chevrolet Maintenance Schedule
Ford, Lincoln & Mercury Maintenance Schedule
Hyundai Recommended Maintenance Schedules
Mazda Manuals and References
Typically, there are two maintenance schedules; one for normal and one for severe driving conditions. 'Severe' conditions include extreme hot and below-freezing temperatures, towing a trailer, driving only short trips, off-roading, racing, etc. The main difference is that the schedule for severe conditions recommends shorter service intervals.
Many newer car (e.g. BMW, Honda, GM) have an in-vehicle maintenance reminder that will display when your next maintenance service is due. One thing to be aware of is that these systems have limited capabilities. For example, in many cars the maintenance reminder system may calculate when your next oil change is due, but it might not know if your engine oil level dropped.
It's also worth noting that industry experts don't always agree with car manufacturers in terms of maintenance requirements. In recent years, car manufacturers increasingly compete for lower ownership costs. As a result, it's not uncommon to see less stringent maintenance requirements, for example, 10,000- or 15,000-mile recommended oil change intervals. However most car experts will probably tell you that your car needs more frequent services.