How to identify your car's fluids and common leaks
Last updated: January 1
It's never a great feeling — backing out of the garage or a parking space and seeing a puddle where your car used to be. Is your car leaking oil? Or, is it some other automotive fluid?
Here are some helpful tips for identifying common car fluids and the potential source of a leak.
Light brown to black: Engine oil
If you see a spot that is amber to dark brown or black in color, it's likely motor oil, says Cars.com. Oil that is older will likely look dark brown or black, says Angie's List — adding that you'll typically notice oil leaks directly under where the engine was.
Oil leaks often come from gaskets or seals in the engine, valve covers or the oil pan, according to Cars.com. It's a good idea to have a mechanic fix the issue before a small leak becomes a bigger one.
Red or brown: Transmission fluid
Sometimes transmission fluid looks similar to engine oil. However, manufacturers add a red dye to transmission fluid so you can identify it, says Eric the Car Guy. As it ages, though, it can turn a darker red or brown. Angie's List notes that transmission fluid typically has a strong smell, too.
Transmission fluid leaks can come from the transmission or the lines going to the radiator or cooler, says Eric the Car Guy. Regardless of where the leak is, it's important to have a potential transmission fluid leak fixed quickly.
Clear, red or brown: Power steering fluid
New power steering fluid is typically clear or red, while it turns brownish when it gets older, says Angie's List. It can be easy to confuse it with transmission fluid, and some vehicles use the same fluid for both the power steering system and the transmission, says Cars.com.
Since it can be hard to tell these fluids apart, it can be helpful to identify where the spots are. If they're near the front, left side of the car, it's likely power steering fluid, according to Angie's List. Check the power-steering reservoir and hoses to see if you notice cracks or leaks or if the fluid is low, recommends Cars.com.
Transparent yellow to brown: Brake fluid
New brake fluid is a transparent yellow (almost clear) but can turn brown as it breaks down over time, says TrueCar. The key characteristic to look for is its slickness — it's very slippery, says Cars.com. You can also check the brake fluid reservoir to see if the fluid is above the required minimum level (see your owner's manual if you are not sure how to locate the reservoir). Cars.com says to inspect the reservoir, too, as you may be able to spot leaks. If you think it is a brake fluid leak, you should have the car looked at immediately as this is a potentially serious issue.
Green, orange, pink or blue-green: Coolant
Coolant is usually easy to identify, as it typically comes in any number of bright colors. Car and Driver says manufacturers use bright colored dyes to make it easy to identify coolant and differentiate it from other automotive fluids. Coolant has a watery consistency and may also have a sweet smell, according to Cars.com.
Car and Driver notes that obvious signs of a coolant leaks include lime-green, orange, pink or bluish-green puddles under your car. You may also notice a sweet smell after you've driven the car, or that the car is running hot or overheating while in use.
The issue could be an easy fix, such as a loose clamp, but it could be also mean something more complicated, like a broken water pump or leak within the heater. It's important to have coolant leaks fixed soon, says Car and Driver, as these problems tend to get worse quickly.
If you've ever seen a small puddle of water as you leave a parking spot, you don't need to panic — especially if you were running the air conditioner. Eric the Car Guy says that condensation builds up in the car's air conditioning as it runs. The system collects the water and then drains it through a small tube under the car, which is why it's common to see drips or puddles of water on your driveway or parking spot on hot days. It's usually nothing to worry about, as it's the air conditioner functioning as intended.
Whether it's a few drips of oil or a bright colored puddle, it can be concerning to see fluids underneath your car. Knowing how to identify common automotive fluids can help you identify the source of the leak and hopefully get the issue repaired quickly