My rear sway bar arrived a couple of weeks ago, and I installed it the next weekend. Taking the old one off was a snap, but putting the new one on was a bitch.
First, the bars have a different bend which places the Addco bar higher than stock, forcing it against the exhuast. I do have an aftermarket exhaust, so I can't complain too much about that. The bar presses so tightly against the exhaust, that it doesn't even rattle. Only I can pick up on the slightly different sound, because I'm used to hearing it on a daily basis. I actually had to get under the bar and bench press it while my roommate threaded the screws.
Second, the holes on the brackets were not large enough for the screws to fit through, and the stock brackets don't fit the new bushings. 5 minutes with a metal file took care of that.
I drove around with the bar like that for a week. It squeaked a lot, but I didn't hear any other funny sounds. I decided to take the bar off and grease the bushings. When I pulled it off again, I found that they eyelets on the bar (which are much larger than stock), were rubbing into the lower arm. When I put the bar on, there was no contact between the bar and the lower arm, but it settled there and started to carve a notch in the lower arm.
I took the bar off and ground the shit out of the extra material around the eyelets. I put the bar back on, and everything sounded great. About a week later, I started to hear an occassional knock sound on hard turns... kind of like the bar was forceably connecting with the lower arm instead of rubbing against it.
I'm going to take the bar off once again, grind it some more, and put it back on. This time I'm going to put tape on the lower arm where the notch is, to see if the bar chews threw it. I also think I'm going to replace the stabilizer end links, because the dust covers have cracks in them. They still rotate smoothly, but I guess it can't hurt.
The Addco web page says that the bar is for the '99-'02, and I have an '03. I wouldn't think that they'd make a change to the suspension setup on the final year of a generation... but maybe they did? Is there something else that can explain my problems?
The bar is centered, and everything is torqued to spec.