I own a second-gen and a third-gen. I've been hammering my '99 Explorer AWD 5.0 Limited for 10 years, and from a drivetrain standpoint, it's a tank! I should be beaten for how little maintenance I've done on this truck in 10 years. Yes, I've had to put 2 front passenger drive hub assemblies on it in that time, and last summer the original alternator finally went down. It still has the original hoses, plugs/wires (I did put a new serpentine belt on it when I replaced the alternator last year). Like I said, I can't complain at all about how much abuse it can take. I also had a popping/clunking/chirping that I decided to look into last summer, that it had been doing for a while and I just ignored it. When I would make a hard 90' turn, especially from a stop, it would make weird noises that reminded me of when running 4WD on dry pavement, like the limited slip was locked and I was hopping the inside rear tire. I decided to check the rear end to see if I was down on fluid. I had 4 quarts of the recommended synthetic oil (about $40 worth), and the LS additive from the Ford dealer. I figured I might be down a little bit. As I added each quart, I checked to see if it was up to full. The book said it only held between 3.5 and 4 quarts. Well, I put all 4 quarts in it and the additive, and still couldn't get it to show on my makeshift checker (a small allen wrench). So I basically had NO fluid in the rear when I started! I have no idea how long it had been running in that condition. The popping/chirping stopped, which I assume was because of the additive, but it still has a disturbing sound coming from the rear end, which I figure is probably extreme gear wear, or a bearing going down. I really don't have the money to rebuild or replace the rear end. We used to take this truck on all our road trips, but since we've got the '05 Mountaineer, the Explorer is "limited" (no pun intended) to shorter trips or just in-town use. What does anybody here recommend I should do, given my financial situation? Aside from these issues, it has been a great vehicle, especially for how little I've done to maintain it. I almost used it as a trade-in for the Merc recently, but they were offering me so little for it on trade that I kept it. I just hope the Merc does half as good for the next 10 years, which is probably what it will have to last for. Thanks for any help!