I have what appears to be transmission fluid running down the two gas lines behind the plastic inner fender. I pulled back the inner fender and the only thing I saw were the gas lines, fuel filter and a wiring harness. It looks like the leak is not coming from the master cylinder which is directly above the opening for the gas lines to enter the engine compartment.

 

BTW this is a 2001 S-type 3.0 with 38K miles

 

There have been several reports of transmission fluid leaks in S-Types at the hoses that run from the transmission pan to the transmission oil cooler up front. Apparently there is a design flaw where these hoses transition from rubber to metal, and they eventually leak at that particular joint. You have to jack up your front end, remove your undertray, and you can then see the mess that's made on the components underneath the engine. There are several threads in the S-Type forum that discuss this problem in detail. Search for a thread called "Exxon Valdez" by JOsworth. I believe he initially posted it in the March 2010 timeframe....

 

So, the location of the leak leads me to ask you a question. Why do you think it is transmission fluid? Is it the color? I'm not sure how your transmission cooling lines are set up since your car has the Ford 5 Speed and not the ZF box. So, I wouldn't concern yourself with my "Exxon Valdez" thread since we are talking about an '01 here and not an '03 and up.

First thing you need to do is pull the belly pan and check for fresh fluid spots. If there is, place the pan on the floor in the same position it would be in on the car to sight where the drip is coming from. Then try to follow it to the source.

Now, there is another component that contains "red" fluid that is close to the master cyl. It is the power steering reservoir. The clamp on the line on the bottom of mine failed and was replaced. That may be worth checking as well.

 

I had a leak from the brake fluid that did something similar. It was going through the master cylinder into the wheel well. It was setting off my DSC and ABS sensor. Eventually I also got an Engine Malfunction light. I would check that also maybe. Only a few fluids in the engine anyway. So it has to be one of them.

 

They are mostly or all different fluids, so commparing to see which one it is will help a lot.

 

The only reason I thought it is transmission fluid is the bright red color - I will check for power steering fluid clamp. The location is what puzzled me, I could not see any transmission lines anywhere close to that location.

 

Also, check all the power steering lines. Let us know what you find.

 

Looked at it again tonight, the expansion tank for the coolant is wedged in there behind the Master Cylinder from the look and the taste of the fluid (yea I know I am old school) it is the coolant. Thanks for all the help so far any idea how to get to that tank, it is under the cowl and behind the MC - bad spot!

 

I would get the JTIS service manual. There is a download for it on this site. Some people have luck with it others not so much. You can also get it on CD off of e-bay for about 10 bucks...

While it is not the most "user friendly" software, it does come in handy.

I find it real interesting that they moved the expansion tank so far. Mine is a post 03 update and the expansion tank is up front by the radiator. Wow, I just looked at a 2001 on e-bay and that side is certainly "busy" the brake system, power steering, and cooling expansion tank all on one side....

 

I am closing this post and opening a new one entitled Expansion Tank Leak