I love my Excursion. I've not had any issues with the air filter like you've had. Was the filter element you removed a light blue color? (The filter medium, not the housing). Light blue is a Ford/Donaldson PowerCore Air Filter. This is the factory air cleaner. A Factory filter can hold over 3 POUNDS of dirt before it is considered full and needing replaced. It has an 05 nose on it, did they change the full clip, or did they use one of the cut down grills to fit the 99-04 bumper? If they just replaced the grill, maybe something that was covered with the original grill is now uncovered and let water into the airbox..... not sure just a WAG!! Looks like a nice truck, I've had mine for going on 7 years and still love it like the day we bought it. If has been fairly troublefree. Normal maintenance - brakes, tires, oil, filters, batteries..... It has a new waterpump and flush and fill, and EGR Delete, and a FICM rebuild and an alternator. I bought it with ~60k on it, it now has ~130k.... so not to bad in my opinion. The EGR delete was done because the blue tube that connects the EGR to the rest of the coolant system started to leak on cooldown. Wouldn't leak when it was cold, at running temp or during warmup, it wouldn't leak if I left the block heater plugged in, but when you allowed everything to cool down, the O-rings in the tube would leak. I was not in a position to fix it at the time, and my local trusted shop was going to fix it, they actually recommended the delete to prevent any problems in the future, and they had to do almost the same amount of work to fix it as do the delete..... so I said lets do the delete. I also, from experience highly recommend using Full Synthetic Engine Oil. I am currently running Chevron Delo 5W-40 since it is the least expensive Full Synthetic I found at the time. It was changed during the long cold winter we just had. My truck had to sit out this winter and we had many weeks in the teens as a hi and I think the coldest I tried to start it was -19F. I kept it plugged in, but it took a longer than normal cranking cycle to start, and there were a couple of days it was +8 or 9 and it just flat refused to start. Once it did start, it was extremely low on power, ran rough and was just generally pissed off to be running, the classic cold engine stiction issue. We had a decent day and changed the oil (15qts of Delo and a new Motorcraft Oil Filter) and the change was IMMEDIATE!! I had no more hard/no starts (still plugged in because of low temps), I had no low power or rough running when the engine was cold, no more stiction issues. I also noticed the injectors are now much quieter when they are operating. Before there was a very distinct injector chatter, along with a separate but distinct diesel ignition rattle. The injector chatter is significantly quieter than it was. Now that it is warm out, the injectors are very quiet, and I have full power and performance (within reason) as soon as I start, I don't have to wait for the injectors to warm up and work right. Synthetic is one of the best "upgrades" you can do for a 6.0L. I have the same issue with the overhead console, over this last winter it has quit working. It does not light up. I have heard it is a resistor issue and there are fixes posted on the net, but I have not looked at this point. I will pull it down sometime and see if there is anything obvious. I have been told they are still available new, I just have not checked on a price at this point. If it isn't too expensive, I may just replace it and see if I can repair the current one and keep is as a spare. I didn't notice, but does it have the automatic climate control, or is it manual. If it is electronic, tuck this in your cap.... Mine failed to power up on a restart, only time it has ever done it, so I posted on here and asked for a fix. I got one. Go out and turn the headlights on and off several times. This resets something in and climate control and it is working just fine again........ You will love the Excursion, mine is my all time favorite vehicle that I have owned. I have no plans on ever getting rid of it, they do everything you ask of them. Have plenty of room for passengers and/or stuff as you have found out. Hook something to the hitch in the back, and it will drag it down the road really well. I had a 21' Travel Trailer, topped out at about 5000lbs. It was so nice to get on the Interstate, set the cruise at the posted speed, kick the AC on max and just drive, and not worry about overtaxing the truck. I am sure it will be your favorite vehicle also. Mine is about the only thing I drive anymore. I have back and knee problems, and it is easy to get in and out of, and the seat is comfortable on my back. On a road trip, if I drive the car (98 Sable Wagon, so not a small car) I can only drive about 45 to 60 minutes before I HAVE to stop and get out, if not, it is difficult for me to get out. I can go a few hours before I have to stop, and I don't have near the trouble moving when I do get out.