Car Maintenance Guide

Brake Fluid 
Engine Coolant 
Engine Oil
Power Steering Fluid 
Transmission Fluid 
Washer Fluid

With the abundance of self-service gas stations, sometimes the only way to ensure your vehicle's fluids receive the attention they need is for you to check them yourself. Maintaining appropriate fluid levels is inexpensive. However, improper maintenance and low fluid levels can make driving more difficult and lead to serious damage and shorter engine life.

If you have a question regarding any fluid not covered, contact a AAA Approved Auto Repair facility or your local AAA club for assistance


Brakes are a critical system on your vehicle, yet brake fluid is one of the most neglected fluids. A quick check of the brake fluid reservoir will determine the current fluid level.

Checking Brake Fluid

  • Before removing the brake reservoir cap to check the condition of the brake fluid, always clean away any dirt or debris to ensure it doesn't get into the master cylinder.
  • Only add brake fluid that is designed for your specific vehicle. This information can be found in the owner's manual and also may be located on the filler cap of the brake master cylinder reservoir. Adding anything other than the recommended brake fluid can damage brake components or cause brake failure.
  • Do not mix fluids. For example, if your vehicle has DOT 3 fluid, then add only DOT 3 fluid. If you are unsure which fluid is in your vehicle, have a AAA Approve Auto Repair facility identify the DOT fluid in your vehicle.

What Should My Brake Fluid Look Like?

  • The fluid should be clear to amber in color (DOT 3 and DOT 4), or have a light purple tint (DOT 5).
  • Dark brown or black brake fluid indicates that it is time to replace the fluid.

Brake Fluid Classification

The Department of Transportation designates fluid grades as DOT 3 and DOT 4 (polyglycol), and DOT 5 (silicone). Most vehicle manufacturers recommend DOT 3 brake fluid for use in their vehicles. DOT 5 is not recommended for use in vehicles that have anti-lock brake systems.


Coolant (also known as antifreeze) prevents engine freeze-up in winter, reduces the engine temperature in the summer, and protects the cooling system from rust and corrosion year round.

Checking Coolant

  • Make sure your vehicle is parked on a level surface and is not running.
  • Always check your engine coolant when the engine is cold, and never remove the radiator cap when the engine is hot. The best time to check the coolant level is before the vehicle has been started.
  • Checking the coolant reservoir is usually all that is needed to ensure the proper level of antifreeze is in the cooling system. If coolant is needed, add a 50/50 mix of the correct type of antifreeze with water to bring the reservoir to the correct level. However, if your vehicle is equipped with a radiator cap, it is a good practice to also check the level of coolant in the radiator, especially if you have a leak or expect a low-coolant condition.
  • The coolant level in the recovery reservoir should be between the minimum and maximum lines.
  • Before removing the radiator cap, verify that there is no pressure in the coolant system by squeezing the upper radiator hose. If you can't easily squeeze it, there is too much pressure in the system. If pressure is present, wait until pressure dissipates.
  • The coolant level should be within one inch of the top of the radiator filler neck, and the coolant should be free of contaminants.
  • Adding a small amount of coolant is normal. However, if you find that you are regularly adding coolant, a leak in the cooling system or engine may be the problem.
  • When changing the coolant, it is also a good idea to have your cooling system's thermostat checked.
  • Coolant should be tested yearly for acid content and to check its freeze protection capabilities.

      What Should My Coolant Look Like?

      • The color of the coolant will depend on which type of coolant you use.
      • If your coolant has lost its coloring or is contaminated with rust, it is time to change the coolant.
      • If possible, avoid mixing coolant of different types/colors.


    Engine oil is one of the most vital fluids your vehicle needs to operate. It works as a lubricant for the engine and as a means of cooling and cleaning internal engine parts.

    Checking Engine Oil

    Your engine oil is the most important fluid to check because running your engine when it is low on oil can result in serious engine damage.

    The best time to check your engine oil is when your vehicle has not been running for a while. If you have been driving your vehicle, waiting at least an hour will give you the best results. This will give the engine time to cool down and the oil will drain back into the oil pan. Cool oil stays on the dipstick better, making it easier to measure the oil level. The cooler the engine, the less risk you have of incurring an accidental burn.

    • The vehicle's engine should not be running.
    • Make sure the vehicle is on level ground.
    • After opening your hood, find the engine oil dipstick and remove it.
    • Wipe off the end of the dipstick with a rag, and notice the markings located near the end of the dipstick. You will usually see a mark for "Full" and another mark for "Add."
    • Insert the dipstick back into tube, remove it immediately, and read the level.
    • If the dipstick indicates the level is at or below the "Add" mark, then add oil. Be sure to add only enough oil to reach the "Full" mark. Do not overfill.

    AAA recommends that consumers change their oil between 5,000 and 7,500 miles, when driving under normal conditions.

    What Should My Oil Look Like?

    • New engine oil will generally have a light gold to brown tint and should be nearly transparent.
    • Synthetic oil is normally darker in color, sometimes almost black.
    • If the oil appears milky or thick, or if it is very thin and has a strong fuel odor, there may be a mechanical problem with the engine. If this is the case, have the vehicle checked by a qualified technician.

    Engine Oil Terms and Ratings

    In 1993, the starburst symbol (shown below) was introduced to help consumers identify engine oil that is suitable for use in gasoline engines. This symbol, along with the American Petroleum Institute (API) and Society of Automotive Engineers (SAE) ratings, will help you identify the correct motor oil that your manufacturer recommends for your specific vehicle.

    API Classification

    This two-letter classification signifies the type of engine (gas or diesel) and the service class. The first letter will be either an S (signifying a gasoline engine) or a C (signifying a diesel engine). The second letter is the service class designator, which has been sequentially assigned since the service classification system started. The letters range from "A" through "J," with J signifying the most recent improvements in the quality of the motor oil. For example, "SJ" motor oil is suitable for use in today's gasoline engines, while "SA" motor oil is considered outdated and will not meet the engine oil requirements for modern vehicles.

    AAA recommends that motorists use the highest designated oil in their vehicles.

    SAE Viscosity Grades

    Viscosity grade ratings indicate the oil's resistance to flow, or "how thick or thin the oil is." SAE (Society of Automotive Engineers) utilizes a numbering system to grade engine oil. An example of a single grade oil is SAE 30, while an example of a multi-viscosity grade oil is SAE 10W-30. (The "W" indicates that the oil's minimum viscosity grade was determined at 0 degrees Fahrenheit, assuring that this oil has been tested and rated for use in cold climates.)

    Synthetic Oils and Oil Additives

    Synthetic engine oils possess performance characteristics that are more desirable than conventional engine oil. However, synthetics should still be changed at the same intervals as conventional oils. Synthetic oils clean better than conventional oils because of their ability to hold more detergents. However, the high cost of synthetic oils makes the benefits far less appealing. If cost is not a concern and you desire protection beyond normal driving conditions, synthetic oils may be for you. For the average driver, the money you save may pay for your next oil change or two.

    Don't Spend Money on Aftermarket Oil Additives that can Diminish Oil Protection. Engine oil comes with additives already blended into the formula. These additives are included to enhance the oil's performance and to help meet the demands required by today's engines. Aftermarket additives often contain the same additives that the oil manufacturers have already formulated into their oil. There is no research that substantiates that adding these "cure-all additives" will provide any greater protection. In fact, by adding some of these products you may actually be detracting from the protection that is already built into the oil.


    Advancements in automotive technology have allowed manufacturers to provide yet another feature on selected makes and models of vehicles -- with a touch of a button it is possible to monitor fuel mileage and actually see how driving habits are saving or costing us at the gas pump. There is another way to save, and that's knowing what type of gas is best for your vehicle. The following information should help you to better understand the fuel requirements of your vehicle and the terms that are associated with gasoline.

    Which Fuel is Right for Your Car?

    The most expensive fuel may not be the best fuel for your vehicle. In fact, "super" or "premium" fuel may actual hurt the performance of your vehicle. Most modern economy cars are designed to operate with minimum octane requirements, while most performance vehicles require a higher octane to operate at peak performance. Simply said, follow the manufacturer's recommendations for your specific vehicle.

    The recommended octane rating can be found in your vehicle owner's manual.

    Octane Ratings and Engine Knock

    The octane ratings that most of us are familiar with are regular, mid-grade, and premium/super. Premium/super is the highest octane-rated fuel. These labels are representative of the numerical octane ratings, and are usually affixed to the fuel pumps on a yellow and black tag.

    Gasoline octane ratings can best be described as the fuel's ability to resist engine knocks. Engine knock (also known as pinging, pre-ignition, detonation and spark knock), is a result of too-rapid or uneven burning of the air-fuel mixture in the engine's combustion chamber. This results in an internal knocking noise in the engine. The higher the octane rating, the slower the fuel burns, and the greater the resistance it has to engine knock.

    Engine knock also can be caused by several other factors. In fact, in most cases an engine knock is a result of a control problem, such as improper ignition timing, carbon deposits in the engine, a malfunctioning exhaust gas recirculation valve system, an engine that is running too hot, or simply an engine that has worn with age.

    If your vehicle is knocking, and all mechanical areas check out okay, it may be time to switch to another brand of fuel. Octane ratings can vary from brand to brand, and simply switching brands may be the answer to correcting that engine knock.

    If the vehicle manufacturer recommends regular gasoline, higher octane-rated fuel will not provide more engine power, burn cleaner or improve fuel economy in vehicles that are in good mechanical condition and do not have engine knock.

    Follow Manufacturer Recommendations

    If the manufacturer recommends that mid-grade or premium fuel should be used in your vehicle, it is important to follow that recommendation. Most modern vehicles are equipped with a sensor that is able to detect engine knock. If a lower rated fuel is used, and engine knock is detected, the sensor will send a signal to the vehicle's computer and the computer will react to that signal, resulting in adversely effected engine performance.

    Quick Tips

    • If you see that a fuel tanker has just finished refilling a gas pump, you may want to try a different gas station for your fill-up. Freshly filled fuel pumps are not your best option because when the gasoline from the tanker is poured into the in-ground tanks, it stirs up water and debris that has settled at the bottom of the in-ground tank. If you fill your vehicle's tank with this, it will most likely contain the water and debris.


    Power steering fluid has special additives to help protect the rubber hoses and seals located in the steering system. Although some vehicles may use automatic transmission fluid, most manufacturers recommend the use of a specific type of power steering fluid. Refer to your owner's manual for the fluid that is recommended for your vehicle.

    Checking Power Steering Fluid

    • The power steering fluid reservoir usually has a small dipstick attached to the cap.
    • Although you can check the power steering fluid when the vehicle is cold, it is more accurate to check the fluid once the vehicle is fully warmed up.\
    • The vehicle should be parked on a level surface with the engine turned off.
    • Remove the cap from the fluid reservoir and check the fluid level. The level should be within the normal range on the stick. Be sure to read the dipstick marking for either warm or cold levels, depending on your engine's condition.
    • If you have to add fluid more than once a year, have the system checked for leaks.
    • If you hear a buzzing noise when you turn the steering wheel at slow speeds, that's a warning sign of low power steering fluid.


    Automatic transmission fluid serves multiple functions. It provides lubrication, keeps seals soft, protects internal parts and acts as a coolant for your transmission.

    Checking Automatic Transmission Fluid

    • Automatic transmissions in recent model vehicles should be checked while the engine is running.
    • Make sure the vehicle is on a level surface with the emergency brake applied, and the transmission in park or neutral. (Check your owner's manual for information on whether your vehicle should be in park or neutral when checking the transmission fluid and where your transmission's dipstick is located.)
    • Raise the hood and locate your transmission's dipstick, making sure to avoid any hot or moving parts of the engine.
    • Once you've located the dipstick, remove it, wipe off the fluid, and re-insert it. Remove the dipstick again to check the fluid level. The level should be within the "Full" range.

    What Should My Automatic Transmission Fluid Look Like?

    • Clean automatic transmission fluid should have a pink tint.
    • Amber to brown fluid is a sign that the fluid may need to be changed.
    • Brown or black, burnt-smelling fluid is a sign of internal failure or lack of proper maintenance. If your fluid shows these signs, consult a AAA Approved Auto Repair facility for the proper diagnosis.

    Manual Transmission and Differential Fluid

    On most models, finding an accessible way to check the manual transmission and differential fluid level is very difficult. It is recommended that service and inspection of these fluids be performed by a qualified technician. Refer to your owner's manual for specific service information.


    When it comes to maintaining your vehicle, adding washer fluid is one the easiest tasks that you can perform. Keeping the washer reservoir full of washer solvent will maximize your visibility by keeping the windshield clean and clear, which ultimately makes driving easier and safer.

    Adding Washer Fluid

    • Always add washer fluid only to the reservoir. Plain water can grow algae or leave mineral deposits that clog spray nozzles. Water also may freeze in cold weather. Washer fluid provides added protection from these elements.
    • Check the owner's manual to verify the location of the washer solvent reservoir. Although the filler caps are usually labeled, it may be hard to differentiate between the engine coolant and washer reservoirs on some makes and models.
    • Most washer fluid is sold in gallon containers. There also is a concentrated formula available in a much smaller container that is mixed with water and is just as suitable as the already mixed version.

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