After having loosened the bolts, Jack up vehicle, and properly secure it with either both front, both rear, or all tires up in the air with a "Safe" and "Quality" jack stand. Don't trust your car, or your life on something you got for $10 bucks. Also, if only working on the front or rear of the car, make sure that it's secured, and won't roll. Block the front or rear, (Tires still on the ground) with the OEM or other wheel blocks.
Now with the car up, completely remove lug nuts, and pull off wheel. The wheel/rim may be rusted to the hub, meaning a few grunts, curses and pounding with a rubber mallet may be required. Here's a pic of the rusty hub. Note.... the calipers had already been removed when I took this pic.
Clean the rust using sand paper, a wire brush or other chemical solvent that you may have. it should look at least this clean after you're done.
Also... don't forget to scrub the inside of the rim, as it may also be rusted.
Now... important. Lithium grease is your friend. It's cheap and readily available from any auto-parts supplier and prevents rust. When done working on your car, before putting the wheels back on the vehicle, apply lithium grease to the hub. Don't do this now, as you'll only end up with grease all over your tools and clothes.
