crazymikey
+1y
First of all,welcome to the site. Good to see another Canadian onboard!
It's quite a possibility that sloshing noise is your fuel tank,especially if you're running around with less than half a tank. You probably didn't hear it before the rain because you has more gas in your tank,lol.
Otherwise,the only place I can think of water getting trapped is in the bed itself and you'd see it,but since you said it's dried up...
Fill up your tank and see if it still sloshes. I know mine does it when I get around a quarter tank.
As for the Xterra rims,are they 6 bolt? If they're 6 bolt and from Nissan,they should probably fit. Many guys including myself run Pathfinder rims on our trucks. I also have an Isuzu Rodeo which is 6 bolt,and I currently have Pathfinder rims on it. 6 bolt GMC/Chev/Cadillac rims fit too. Escalade chrome rims are a popular mod,but the centre of the rims need to be drilled out a bit to clear the hubs. Z71 rims will bolt right on.
Give the Xterra rims a try. If they're the gunmetal 4 spoke ones,they would look killer!!
I'm also planning on lowering my truck in the spring, using AIM drop spindles, the Belltech leaf kit and Toxic drop shocks.