Eric:
I'm willing to bet money that the squeak is your front sway bar mounts to the body. The factory mounts on my 2000 X were beat to a pulp...looked like they'd be better suited to hold an egg rather than a sway bar. I always sell greaseable polyurethane sway bar bushings from Energy Suspension when I sell Addco bars for the Jeeps, so I purchased a set for my Excursion as well. Not only was the intermittent squeak gone, but the X turns a lot better because the sway bar isn't flopping around aimlessly inside of the sway bar bushings. I had to modify them to fit, as the Ford bushings are a crazy shape and have a longer leg to make up for the "hump" on the frame rail that tensions the factory rubber bushings (for the first few ten-thousand mile segments). Seems like I had to not only place a flat washer or two between the frame rail and the bushing housing, but also had to drill the holes out slightly in order to get them to fit. Oh, no...I take that back. I had to replace the 10mm sway bar bushing mounting bolts with longer ones...35mm long, IIRC, so that they would be long enough to use with the flat washer spacers I used.
Anyway, it's a VERY good mod. Now, if my bar squeaks, I hit it with a shot of grease, which shuts it right up for months again. You can have your lube-shop guy do it when they swap the oil, too.
A loose shock mount will make a "thump" sound, not a "rattle", so I'm guessing it's not a shock. Is your exhaust hitting something, by chance? Grab a pair of gloves, grab the tailpipe tip, and shake it around. Any noises? Could the third motor mount (the tranny mount) be going bad, allowing the tranny to hit either the crossmember or maybe the bellhousing against the body? Just ideas...it's hard to hear the noise from Phoenix, lol.
Hope that helps!
Kevin
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