lowering kits

i have an 07 colorado but im not sure what kind of suspension i have. my truck is just the basic work truck cause thats all i could afford at the time seeing as i am a college student. but all of the kits that i have seen so far are for the z85 or zq5 suspensions. how can i find out what i have because i have looked on all my tags and cant find anything. i have also used a vin decoder which didnt tell me anything really. any help would be very appriciated.
 
 
thanks
azcolorado

You should have much difference in any of them. The 4x4 suspensions are torsion bar suspensions and the 2wd suspensions are frontal coil and rear leaf.