The human body is made up of 75 percent water. Although it doesn’t look like it, we are mostly fluid. The same cannot be said about your car. However, there are a lot more fluids in your car, moving around inside, than you would probably expect. And as with the human body, these fluids are all incredibly important to maintain the normal and healthy operation of your car.

A Guide to the Fluids in Your Car and How to Top Them Up

Here we will take a look at the various types of fluids in your vehicle and how you can top each of them up.

Engine Coolant

Engine coolant is used in order to keep your engine cool and to prevent it from overheating. It’s very important for this reason but doesn’t usually need topping up as often as some of the other fluids. It’s worth checking regularly to be sure. Typically, you should be okay to leave it until each service.

When you do check/top up your engine coolant, you need to first bring your car to a stop and then let it cool down. This is very important for two reasons.

  • If you don’t let the car cool down, then the water will expand and thus the reading will be inaccurate
  • If you remove the cap when the engine is hot, it can cause scalding water to spray out, leading to serious injury

Once the car has been resting for a while, find the coolant cap by referring to your manual. You should find that you are able to locate a minimum and maximum level and to see where the coolant comes between those marks. Ideally, the coolant should be filled just halfway between those two levels.

If not, mix the coolant and water to create a solution that’s about 50/50 and then pour it in. If you notice that you keep having to top this up, it may be that you have a leak and should take your car to the garage. A leak can occur at any pipe or in the cooling system.

Screen Wash

The screenwash is one of the less mysterious fluids in your car but is nevertheless very important. The role of screen wash of course is to let you wash your windshield. You need a mixture of water and wiper fluid to remove any grime or dirt.

To check your levels you again need to look for the markers. To fill it up you again need to pour your solution into the cap, often located by the windshield. The precise location can vary so do check your manual if you’re unsure (pouring the wrong fluid into the wrong cap can be disastrous).

Usually, you will want to use a solution of around 1:2 where you’re using twice as much water. This will prevent the wipers from leaving a trail of sticky residue which can happen if you add too much soap comparatively.


The role of engine oil in your car is to lubricate the parts, help keep the engine cool, and act as a sealant. It’s very crucial and if you run too low then you can end up with engine issues.

To check oil levels you need to use a dipstick. You can locate this within your engine by finding the round or ‘T-shaped’ handle. Pull-on this and a long stick should emerge covered in oil. What you need to do now, is to wipe the end of the stick and dip it back whence it came. Now examine how high the oil comes up on the stick. It should be just between the minimum and maximum levels. If it isn’t, then find the oil cap – usually made clear with the word ‘OIL’ emblazoned on it – and then pour some oil in. Check the levels as you do and stop when it’s at the right amount.

Brake Fluid

This is another one that you won’t have to worry about too often, but that you should nevertheless take care to check on regular intervals. Low brake fluid can often be very dangerous and so it is normally changed about once every two years. Various factors can influence this though, so be vigilant and check often.

The reason brake fluid is needed is that braking systems are hydraulic – using fluid to create pressure that pushes the various parts around inside. Hydraulic systems are better than pneumatic in this instance because fluid cannot be compressed whereas air can.

The brake fluid reservoir can be found under the bonnet and is usually just on top of the brake master cylinder – the first hydraulic part of your braking system that is responsible for applying pressure to the fluid initially.

Oh, and don’t forget the gas!

Dave & Rays Automotive Repair Shop in Omaha, NE

Our team has learned one thing: automotive problems are as varied and unique as the customers who bring them to us. Fortunately, our decades of experience in auto service and repair also mean that our skilled network of professionals is ready to accommodate an impressive scope of automotive issues. Contact us today.

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