Factory Keys

[hanrock]

hi whats with the color codeing on the factory keys just different applications or what. ive been looking at diferent lift options for a while now and probably just going to level my 08 2500 hd 4x4 suspension lifts are out of my range i turned the keys some already 1.5 ish truck still sits 2" lower from front to back and driver side key is almost maxed ive noticed some new trucks seem to sit higher than mine from factory so i might go up a little more bought new wheels today 16x8 with -6 offset and they will rub a little at full turn backing down a small incline just curious abought how far to go and if gm has different index keys [different color codes] then whats the answer...... any and all opinions welcome thanx