Yellow Fluid

Just had a large ice storm and noticed a yellow fluid leak underneath my car on drivers side near the real wheel. In my research I’ve found it’s either coolant or break fluid. How do I go about figuring out which it is?

There’s a third possibility. Don’t eat the yellow snow.

Check your fluid levels. And test your brakes. Your brake pedal will sink to the floor if you have a leak.

See if you can get some of it on your fingers. Brake fluid is oily and antifreeze smells sweet and is also oily…HOWEVER anti freeze has no business back there so that may just be evidence still left behind from a previous persons car.
Also if you are leaking brake fluid you will quickly notice an issue with your brakes. Your brake pedal will begin to go further down twd the floor and you will have reduce braking power. You will notice this rather quickly if you have a leak so…if it is brake fluid you prob already know it.

Perhaps an area dog has lifted his leg and left the yellow fluid while on a walk?

You Possibly Have A Road Salt Leak. I’m Serious. I Used To Freak Out About Yellow Fluid In The Snow Under Parts Of My Car, Until I Tasted It.

I had occasional yellow fluid leaks where there’s no fluid to leak, no doggy footprints, no low fluid levels, red coolant, so I taste tested it. I can’t tell you why liquified road salt appears yellow, but it does when it falls on snow or ice from the car.

I still freak when I see these yellow drips, but soon relax when I realize what I’m looking at.


If “near the real wheel” means “near the rear wheel,” you can rule out coolant.

Brake fluid is non-water based, doesn’t evaporate, and if leaking is likely to adhere to your rear wheel hub/inside of rear tire.

That’s why one does not eat the yellow snow…

I’m still betting it’s the neighbor’s dog.

I agree with CSA on this one. I moved one of my cars yesterday and spotted a line of yellow drips on the snow where the car was parked. There are no fluids in my car that are yellow, and there were no animal tracks under the car. Considering I had recently returned from a long trip on the PA Turnpike, where they use LOTS of salt and other chemicals, I concluded it was the salt that made the yellow spots.

Even if your coolant is yellow, how would it drip from the rear wheel area?

[b]  Until I Tasted It. [/b]  

CSA, you certainly are one of the most car knowledgable people I know, but . . . . identifying an unknown liquid by tasking it ???

I Have Played With Mercury, Worked In A Car Dealer When Brakes And Clutches Were Asbestos And Mechanics Used Non-OSHA Approved Air Guns To “Blow Them Out,” Run With Scissors, Raced Dune Buggies And Dirt Bikes Through The Woods (Have Tropies), Raced Down The Rockies On Skiis, Raised Two Kids (as tough as all this), Soloed Airplanes, Survived 1/2 Million Miles In Old Beetles, Burned Off my Eyebrows Looking Down Carburetors And Revving Engines, Lived Through 7 Motorcycles, Scuba dived, Siphoned Gasoline With A Hose And Gotten A Mouthful, I Still Run A Sea-Doo In Adverse Weather, . . .

. . . What . . . is tasting something that I keep seeing under my car bad ? I’m actually getting better as I age.


Yes, it’s an animal, and remember that not only dogs produce yellow “leaks.” So do cats, raccoons, possums, and whatever other critters inhabit your neck of the woods.

It is brake, BRAKE, B_R_A_K_E !!!

C- oldtimer, incomplete sentence.