A Guide to Checking Your Car's Fluid Levels

Ellie Dyer-Brown, 3 months ago

5 min read

  • Maintenance
  • How to
  • Car ownership
Woman topping up car fluid in high vis vest

WhoCanFixMyCar explains how to check and top up your car's fluid levels.

Cars are designed with incredible skill and are built to last for years. But without proper lubrication, many vehicle components can fail well ahead of time. That's why it's essential to familiarise yourself with the fluids your car needs, how to check them, and how to top them up.

This guide covers everything you need to know.


Engine oil

Transmission fluid

Engine coolant

Power steering fluid

Brake fluid


How to check engine oil

Engine oil is essential for reducing the build-up of friction between the hundreds of rotors, pistons and gears in an engine.

Woman checking engine oil

Checking the oil level in your car is a simple process that you can easily do yourself. Here's how:

  • Locate the oil dipstick. You can usually find it near the front of the engine. If you're not sure, check your owner's manual.

  • Remove the dipstick. Wipe the excess oil off with a rag.

  • Put the dipstick into the oil. Then, pull it back out to get your reading.

  • Check the oil level. There will be two clear marks on the dipstick, minimum and maximum. If the oil mark is between the two, the level is ok, and you won’t need to top it up.

  • Top up the oil as needed. Running your car with insufficient oil can lead to engine damage.

Regular oil checks are crucial for the health of your car's engine. Older cars should be checked more frequently as they tend to use oil faster.

You should also aim to change your engine oil at the correct intervals, which involves draining the system, replacing the filter, and filling it with fresh oil. We explain how to do it in this guide, but if you don't feel confident, a mechanic will be happy to do it for you.

The average price of an oil change is £104.50, according to WhoCanFixMyCar's data.

How to check transmission fluid

There isn’t always an easy way to reach the transmission fluid. Some cars have a dipstick, so you can follow the steps above to check the fluid level. However, many vehicles require the help of a mechanic to locate the reservoir, perform the necessary checks, and top it up.

Signs of low transmission fluid

Since you might not be able to check the transmission fluid yourself, it's a good idea to learn about the symptoms of low fluid, which include:

How to check Engine Coolant

Coolant is one of the easiest fluids to check and top up. The reservoir should be visible when you open the bonnet, and the lid is usually labelled. On the side of the coolant reservoir, you will see two lines, one indicating the maximum fill point and the other indicating the minimum. The coolant level should sit somewhere between the two.

Engine coolant

If it needs topping up, use the correct coolant for your car. You can find this information in your owner's manual. Wait until the vehicle is completely cool, then pop the lid off the reservoir and pour the coolant up to the correct level. Finally, replace the lid, making sure it's secured. Using a funnel is an excellent way to prevent spillages.

How to check power steering fluid

Power steering fluid creates a hydraulic link between the steering wheel and front wheels, making turning much easier. Topping it up involves a process similar to that of engine oil.

  • Locate the reservoir. In most cars, the power steering reservoir will be towards the rear of the engine bay on the driver's side and will be clearly labelled. It might be metal or plastic. Consult your owner's manual if you're not sure.

  • Check the fluid level. If the reservoir is made of see-through plastic, it should be easy to see whether the fluid is between the maximum and minimum fill lines. But if it's metal, you can use a dipstick.

  • Top up the fluid. Make sure you use the correct one - most power steering fluids are red and clear. A funnel will come in handy to avoid spillage. Don't let the fluid go above the maximum line as you pour it.


How to check brake fluid

As discussed in this guide, brake fluid is a crucial part of the braking system. Most manufacturers recommend changing it at least every two years, and you should check it between those intervals, too. Here's how.

  • Find the brake fluid reservoir under the bonnet. Your owner's manual will tell you the exact location. It is usually white, and you should be able to see the dark fluid through the plastic.

  • Note the fluid level. If it falls below the minimum fill line, you should top it up and arrange for your brakes to be checked as soon as possible.

  • Remove the reservoir cap. It's a good idea to clean it beforehand to stop debris from falling inside.

  • Add the fresh fluid. Top it up to the maximum fill line, then replace the reservoir cap, checking it's secure.

  • Drive a short distance. Brake every so often during this journey. When you get home, recheck the fluid level to ensure there hasn't been any drainage.

This guide discusses how to change brake fluid in more detail.

A car's brake fluid reservoir

If your brake fluid is low again shortly after topping it up, there may be a leak in the system. You should have your car checked by a mechanic.

Here are five brake problems you shouldn't ignore.

How to check screenwash

Topping up screenwash is the easiest job of them all. All you have to do is locate the reservoir and fill it upto the top. The risk of spillage isn’t a major issue as the fluid won’t damage anything that it comes into contact with.


Learn more about the process of topping up screenwash in this guide.

Do your car's fluids need changing? If so, WhoCanFixMyCar can help you find a reliable local garage to get the job done.

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Written by Ellie

Ellie Author Pic

Ellie is WhoCanFixMyCar’s Content Writer. She has a BA in English literature from Durham University, a master’s degree in creative writing, and three years of experience writing in the automotive industry. She currently drives a Suzuki Swift.

Find Ellie on LinkedIn.