Clay Bar Help!!
Also, pressure doesn't matter, the harder you push, the more road enviroment your going to get off. However, if you have a black car, you are more likely to leave scratches in the paint (towel like scratches). While all cars benefit from clay bar, it is most noticable when i white or light colored car needs to be clayed because of the tar, rail dust, road grime, and whatnot that is most noticable to a light colored car.
Finally, it is not necessary to wash a car after claying it. i wipe off the lube residue as i go. but if i don't feel like wiping it off as i go, i just wax over it all when im done. buff everything off with 2 microfibers. (apply wax one panel at a time with an damp applicator, then use 2 microfibers, one for the initial wipe off, then another to "buff" the smears and smudges to a brilliant shine)
And remember, anything you do is better than nothing! If you "screw" up the process, you have still put in more effort than 99% of my customers!

