The below information is not trying to tell you what to do - just advice that can be taken or not. Just things that I have found that work for me.
Just wanted to give an update; The source of the oil leak is the driver side valve cover... and possibly the timing chain cover :( -- I also found a leak from the upper transmission fluid line where it connects to the radiator, so I'll have to put a splice in there or replace that line YAY!
Almost always, the transmission cooler line leak is fixed by tightening the clamps on the two lines where they hook to the radiator nipples. The lines themselves are very tough as far as not cutting through.
The clamp screw heads are very hard to get to - you might actually save time and frustration by removing the radiator fan assembly. It's a tight squeeze getting the fan assembly by the upper and lower radiator hoses, but can be done carefully without disconnecting the hoses - hint: move the fan assembly back towards the engine so you can flex the hoses out of the way rather than be blocked by the rigid radiator nipples.
If they used the same clamps on your '02 as they did on my '98 and '99, the best tool to tighten those screw clamps is a 1/4" open-end wrench - any other type of wrench is problematic due to socket and box-end walls being too thick to fit between screw head and clamp band - also, the screw head hex corners are rounded and not sharp, so the 1/4" wrench needs to be a close fit - for that reason, even if you could get a socket or box-end on, if it was 12-point and not 6-point, it would slip.
Again, should be good just tightening the two clamps, but you could replace them with fuel injection hose clamps (available at NAPA stores) - they give a nice even pressure all around and so are more effective at preventing leaks with less severe tightening that could cut thru a hose due to uneven pressure of the screw clamp. You just need to get the right size. The hoses can be difficult to remove from the radiator nipples (to put the new clamps on) due to the barbs that slightly cut into the ID of the hoses.
Fuel injection hose clamps:
I started on the thermostat/housing this weekend because I really wanted to do something other than the valve covers again.
As far as that job goes, it is a classic case of "Don't read the FSM"... I started removing the lower radiator support, ran into some issues with a stripped bolt (wasted a good amount of time on that one).
So I started looking it over for another route... May have required a bit more work but it allowed me to access everything I needed while standing up and not risking dumping antifreeze on my face. I removed the power steering pump, alternator and tensioner bracket... Much easier to do the job from there
No easy way to do it. Alternator and p.s. steering pump R&R are difficult on the 2.7. I believe the FSM procedure does have you remove the alternator anyway.
I tested my thermostat and it is good so I'll reinstall that one with a new gasket and replace the housing because I had to use a knife to cut the lower hose off of it. I'll also replace that hose with a longer one that will go over the rusty spot and hopefully get me to Spring when I can replace the metal line. Replacing the cruddy spring clamps because they're a PITA to take off even with all that stuff out of the way.
You might still replace the t-stat. OEM only and test before install. I'd trust a new OEM one over a years-old one, especially if it's the original (meaning *very* old). Up to you.
I prefer the factory spring clamps because they are "self tightening" when the hose rubber takes a compression set, plus the even pressure all the way around. For the future, you could get a cable-type spring clamp tool - about $30-40 for a decent one. Even then, it can be a little difficult getting the spring clamps on and off with that, but usually there's a way - it makes the near impossible fairly possible (though not always
Don't know if we discussed, but you may otherwise already know: Only G05 (HOAT) antifreeze, thorough flush, no mixing with other types, use distilled water.
• Chrysler/Mopar Long-Life 100k Mile (reddish in color)
• Zerex G05 (yellow in color)
• Ford/Motorcraft "Gold" (yellow in color).
Did you actually figure out where the water is leaking from?
Cable-type spring clamp tool:
Bit off more than I could chew in one day (Saturday was nasty, cold, and windy here so I didn't do anything), so she's parked for the week. I'll use my long weekend after Thanksgiving to put everything back together and replace the valve cover gaskets (got FelPro -- hopefully that brand can be trusted for this application?)...
Felpro or OEM are always safe on the gaskets. I just haven't ever had to use any other brands, and don't feel like learning the hard way which other brands are good and bad. Felpro is one of the few companies still around that has earned a solid good reputation. Have never had a bad experience with them, and have never heard anyone bad mount them - very unusual. Digikey Electronics and McMaster-Carr are two other companies like that.