Mystery leak

About a week and a half ago I had to have my radiator replaced. After the work was done I have noticed a small fluid leak that is occuring. The leak does not occur until well after the car has cooled down. The amount of fluid leaked out isn’t that great. The location of the leak is very nearly underneath the radiator. The fluid is not antifreeze or water. At first I thought it was maybe transmission fluid, but with close monitoring, I can see I am not loosing any of that fluid, nor oil. I did have to put some power steering fluid in. Could that be the leak? What other fluids could be causing this?

The only fluid left is brake fluid. But the symptoms don’t indicate that as a possibility. Brake fluid leaks very quickly of you develop a leak, and you lose your brakes.

Since you had to add power steering fluid, my guess is that’s the system to look at. The most common places for the PS system to leak are the rack and the pump. Hopefully yours will be the pump. That’s way cheaper to change.

It could the the power steering, but the transmission is more likely. Please be aware that the transmission holds a lot of fluid. A small leak will not be detectable via the dipstick until it has gone on for several months.

In hindsight, I agree. perhaps the tranny cooler lines are the first place to look. Although I believe that on this car the cooler is seperate from the radiator, I’m sure they had to fiddle with the tranny cooler when they replaced the radiatoor.

I agree with Tardis. Many transmission coolers are integral with the radiator, and if a fitting is not tightened correctly transmission fluid can leak. When everything is cool, feel around the transmission cooler line connections and see if one of them is leaking.

Even if the transmission cooler is separate it’s located very close to the radiator, probably just in front of it.

The fact that you’ve had to add PS fluid, however, means you should check the PS pump and associated hoses closely.

I hope you’re looking under the hood and not guessing about where the fluid is coming from based on the location of the spot on the garage floor.

I basically check all my fluids about 2-3 times per week. I make sure all are up to the levels required. I have not had to fill any but the power steering fluid since I got the car and the power steering just once and that was since I had the rad replaced. Knowing what a loss of transmission fluid can do, I monitor it very closly.

Btw, how do I tell what type of transmission fluid I need for my 1998 Ford Taurus SE 6 cylinder/3.0 engine? I don’t have an owners manual.

A man that checks his fluids 2-3 times a week,hmmm…could be good or could mean obsession.

Could be both…could be an obsession that’s good.

Given the state of the engine (believed to have a blown headgasket) and such I try to keep on top of all fluid conditions. I have to add about 2-3 cups of antifreeze to it each week due to the pressure blowing AF out of the overflow jug, so I just check the other fluids while I am there.

Since you didn’t tell us the year, this vehicle wouldn’t by chance have a power steering fluid cooler mounted in front of the radiator?


Its a 98 Ford taurus SE stationwagon. The PS area where I put the fluid in is not in front of the rad, but sits over near the alternator.

You can find what system is leaking by pouring a dye into each one and observing any leaks with a UV, or blue, light. Here are the dyes

I looked it up. There IS a power steering fluid cooler in front of the radiator. If the leak is at the radiator area, and you’re adding power steering fluid, the power steering fluid cooler is probably what’s leaking.