Fluid Leaks 101

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Do you have a fluid leak under your car or truck? Here’s a simple way to be your own private investigator. If you’re not sure whether you are losing oil, transmission fluid, coolant, or brake fluid, here is a simple, but effective method for finding who or what caused it!

Place an old sheet or large piece of white cardboard under the vehicle overnight. In the morning you will have your answer. Each fluid is a different color to help you diagnose the answers.

If the leaks have the following color, you have a good indication of what fluid you are leaking.

Bright Green:Radiator coolant, this is also very slippery to the touch.
Light or Dark Brown:If you change the oil often it will be a light brown, if not the fluid will be a darker brown. Make sure to change your engine oil every 3-5000 miles.
Bright Blue:Windshield washer fluid. (Winter washer fluids can be orange, pink or yellow).
Light Brown:If there is also a strong odor of rotten eggs, this is 90 weight or gear lube. It may be leaking from
the rear axle center section or the manual transmission.
Red Fluid:Automatic transmission fluid or power steering fluid. Note where the fluid is coming from – it
could be long life coolant.
Clear:Power steering fluid or water from the condenser on the A/C unit.
Light Yellow:Brake fluid is light yellow when new as it absorbs water the fluid becomes a dark muddy brown.
Brake fluid absorbs 2% water over a one year period under normal braking conditions. This is a
very important fluid and should be changed every other year.
Amber:Gasoline, but there will be a distinct odor.

The location of the leak could also be a dead giveaway. Being a good sleuth make it obvious to conclude that there will not likely be an anti-freeze leak in the back of the vehicle.

The government tints fluids different colors for safety reasons. This will assist you during maintenance schedules too.

Keep a sharp eye on your vehicle; leaks can be frustrating and even dangerous. If you’re unsure go to a professional certified mechanic and ask for help. Even James Bond will ask for help at times.

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Lauren Fix

Automotive Expert

A highly credible automotive and lifestyle expert, Lauren Fix provides solid information on safety, and a wide range of automotive topics and issues. Her motivational speeches as the Carma Coach will help you find the vehicle that gets you where you want to go.

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