Car Leaking Fluid? Identify It by Colour

The short answer

Brown or black is engine oil. Green, orange or pink with a sweet smell is coolant. Red is transmission or power steering fluid. Clear and slippery near a wheel is brake fluid, and that one means do not drive. Clear water under the front on a hot day is just the A/C.

Brown or black, oily

Engine oil. Fresh oil is amber and it darkens with use. Small seeps from gaskets are common on older engines. Check the dipstick: if the level is dropping between oil changes, the leak needs fixing. Oil dripping on a hot exhaust makes a burning smell.

Green, orange, pink or blue, with a sweet smell

Coolant. It usually drips near the front of the car, from the radiator, a hose or the water pump. A coolant leak leads to overheating, and overheating does real damage to an engine, so watch the temperature gauge and get it looked at soon. Coolant is poisonous and tastes sweet to pets, so clean up any puddle.

Red or reddish brown

Transmission fluid or power steering fluid. Transmission fluid usually drips under the middle of the car. Running a transmission low on fluid causes slipping and expensive wear.

Clear to yellowish and slippery

Brake fluid, most often found near a wheel or under the driver's footwell area. A brake fluid leak can mean losing braking on that circuit. If the pedal feels soft or sinks, do not drive the car. Have it towed.

Clear water

Water dripping under the front passenger side in warm weather is condensation from the air conditioning. It is normal. Water dripping from the tailpipe on a cold start is normal too.

Blue, thin and watery

Windshield washer fluid, from a cracked reservoir or a loose hose. Not urgent, but you want washer fluid in a Toronto winter.

How to check where it is coming from

Slide a flattened cardboard box under the engine overnight. In the morning the spots show you the colour and roughly where the leak is. Take a photo and send it to us by text.