We sell haeps of truckwash at work and as a rough guideline,
CT18 the green one, is the most agressive, good for chassis,under carrage,engine bays etc..
But will dull paint if used to much.
RL18 the blue one, is a good allrounder i use it for the camper,house, under 4wd, patio etc....
It will also dull paint but not as bad as CT18.
CT20 the yellow one, this is the princess truckwash has a wax in it and is ok to use on painted panels.
not as good as the above 2 for heavy cleaning but good enoungh for regular washing of vehicals etc...
Cheers Ian.