So it would appear I have a small leak on my truck. I am getting little yellow spots under the engine. I crawled under there and didn't readily see anything. Granted it was 15 degrees and in the snow, so I didn't look long. That said, my antifreeze is red, so I'm wondering what this could be from. Thoughts on where I should start looking?

 

Yellow... hmmm.... What color windshield washer fluid do you use?

Unless you parked where the Huskies go.

 

Just the standard winter peak blue. I know, the yellow has me stumped. The only thing close I can think of is Etheleen glycol, but this truck doesn't use that. Battery acid? Isn't that clear. I don't even know where to start. I'll keep hunting..,,,

 

What year is your truck?

 

It is a 2015

 

My guess is coolant.


It could look yellow.

 

Coolant would be my guess as well though the fluid level is exactly where it should be. I checked everything underneath and didn't find any spots that looked like they were leaking. I'll check again and maybe a bit more thoroughly.

So the red coolant can turn yellow?

 

Ok, so you are using the blue stuff. I have a bunch of the rain-x orange/yellow stuff... And prestone makes a yellow washer/deicing fluid too.

Take a little coolant out of the degas bottle and look at it to compare to the color you are seeing.

A slow leak you won't notice a difference right away in the degas bottle. These trucks hold a lot of coolant. Mine moves in the degas bottle several inches depending on the temp too...

Here are areas coolant typically leaks from as I have seen them posted in the forum, from most common to least common:

1. Main Radiator - lower side where there is a fitting or coming off a corner.

2. Water pump

3. Coolant line to Turbo.

4. EGR Cooler.

5. Which was my case on my 2011 truck, someone topped the coolant off a little too much and it shoots out of the pressure relief in the degas bottle coating the underside of the hood with coolant.

--

Not sure of the hue of yellow you mean, but could it be power steering or brake fluid? I'll have to look at mine to see what color they look like.

One other quick question, are you looking at the color of the fluid under white light or that orange high pressure sodium vapor lights they use as street lights around here? (or was this during the day?)

 

Battery acid is clear, but of course it'll corrode things on the way down and it could turn yellow. Easy to check the batteries. And if you are cranking fine, I doubt it's them.

Part of our mutual problem is that there is still a lot of water/snow/slush on the roads. I can tell you mine drips for hours after I park it as I see all the snow/slush/mud drip down in the garage. If you just changed your oil, new oil is kinda yellow/gold in color. If you dripped some filling it up... As soon as you run oil in these, of course it turns black... So it wouldn't be an active oil leak from a lubricated by oil part.

 

On my 2011 I used to see the yellowish drops in the winter too, even though during the summer, it was always dry under my truck - i.e. no leaks. It always puzzled me too. I felt like it was fuel, since around here they add the greenish dye to diesel fuel. I never tried to analyze the spots, as in the touch/smell to try to figure it out.


EDIT: I only ever saw them in the snow, never on bare pavement. although that would be hard to notice.

 

After an hour on the ground in the snow in our 10 degree weather, I finally figured it out. Looks like I'm getting a small amount of bypass on my steering stabilizer. It is dripping in low amounts through the boot, which is why it was so hard to find. Turns out the oil is yellow. Guess I'm getting new stabilizers once it warms up. Glad that is solved, it was driving me nuts.

 

Do you see the drips soon after parking the truck?

Is this something you find after it sits overnight?

Could it possibly be a rabbit or critter sitting under the truck after you park it for the night?

 

Good to know. Thanks for sharing

 

I assume your are still stock shocks...

FWIW, when mine go, I am upgrading my steering stabilizer and shocks. Ford stock ones are not that great.

 

I second Dak's remark here. The factory shocks were horrible, but I didn't know that until changing them and the steering stabilizer to Bilsteins after I had a shock go bad coming home from the G2G in Wisconsin. PLUS, the Bilstein 5100 steering stabilizer stopped the "death wobble" I had from time to time while towing. Now the ride is much improved!