How To Check Fluids in Your Car

Ideally you want to check fluid levels once every two weeks but no less than once per month. Every major component of your vehicle, the transmission, cooling system, brakes and engine rely on fluids to function properly. Checking the fluid levels regularly will help keep your car humming along and just as important, can identify potentially severe problems that need to be addressed.

• Paper towels
• Owner's manual
• Clean shop towel
• Grease cutting cleaning solution
• Flashlight or shop light

The location of fluid filler caps will vary from car to car based on manufacturer, model and year. The first step in checking your fluids is locating and identifying where they are. The information you need will be detailed in your owner's manual but it probably won't be as easy as "look and point" to find these locations particularly if you have a car with some miles on it.

The inside of your engine compartment will probably not be as clean as the one the manual uses for demonstration. In fact some of these locations may be nearly invisible thanks to a buildup of grime. Before you start your checking routine, find the filler caps and clean them to the point you can read any markings on them. You may need a flashlight to assist in finding them and reading the measurement lines.

1. Identify the location of the filler caps for window washer fluid, engine oil, coolant, brake fluid, power steering fluid and transmission fluid.
2. Windshield Washer Fluid. The filler cap is usually at the front of the engine compartment and the top is marked with an international signal for windshield wiper. To check the level just lift the plastic top off and look for the fluid. If it's low, fill to the top.
3. Engine Oil. Try to do this first thing in the morning when the engine is cold. Locate the dipstick, pull it out and wipe it clean with a paper towel. Reinsert the dip stick and then pull it out again. Holding the stick horizontally see where the oil comes to on the stick. The stick will have markings for "full" and "add oil." If the oil level is between these two markings you are good to go and no oil need be added. Some Japanese models have two holes rather than markings on the dip stick. The top hole is "full" and the bottom hole is "add oil."
4. Coolant. Here's what you don't want to do. Don't remove the radiator cap while the engine is hot or even warm. The safe way to check coolant is to use the coolant reservoir which is a big plastic container located near the radiator. On the outside will be lines marking where the coolant should be when the engine is hot and when it is cold. Use only the coolant that the owner's manual recommends to top off. Don't mix brands.
5. Transmission Fluid. If you own a late model car you may not be able to check this as many manufacturers are requiring it be done at the dealer. For everybody else (except Honda owners) you need to check this fluid while the engine is running. Like the engine oil the transmission fluid has a dipstick that you remove, clean and reinsert. After you have cleaned the stick pull it again and look for the fluid level. Like the motor oil it should read between the "add" and "full" marks.
6. Brake Fluid. Brake fluid level can often be read on the outside of the master cylinder which is typically a translucent white plastic. Some may have a short dipstick attached to the cap. If you notice that after you have topped off the fluid it is low again on your next check you may have a leak in the line and you need to inspect it.

As a general rule never overfill a fluid as that can do as much damage as running low on a fluid. Change your oil and flush your coolant per your owner's manual schedule. Keeping an eye on your fluids can save you an expensive repair.

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