Now, I've read the other reviews on this 2000 model year Explorer. I am being honest here when I say that I have not experienced any of the major mechanical or electrical problems that others have witnessed. I am either blessed - or perhaps I'm the exception! I have the fully loaded package, right down to the powered leather seating, sunroof, and compass/thermometer gauge (like I really need that in Hawaii). And YES I do take this truck off-roading - no rock climbing, but we do have some poor trails that literally beckons for SUV's to travel on. And I drive off-road with a set of BF Goodrich's, with no modifications to the suspension - kept everything stock.
By the way, I have used synthetic motor oil in it (AmsOil 10W-30) and an accompanying AmsOil oil filter from the very first day I owned it (after I drained the stock fill, of course). Being synthetic, I have run the same oil and just changed the oil recently at 30,000 miles. No leaks, either, contrary to what a lot folks think of synthetic oil getting past the seals.
I also fill up with 87 octane fuel from Chevron, religiously.
I'm keeping this Explorer - it rides well for a truck, no interior defects (save one), and has cost me little to maintain.