You would think these trucks would be more uniform. As far a having steel and aluminum control arms on the Z71s I wonder if it is depends on if it is an GMC or Chevy. I know that all the GMC Crew Cab Z71s I have seen have had aluminum have not looked under to many Chevys. I do know all Double Cab and 4X4s in the GMC line that I have seen have steel control arms.
I'm also starting to wonder if the models such as LS, LT,LTZ or SL, SLE, SLT have anything to do with what trucks get the steel or aluminum control arms and are the ones coming with the max tow, denali or high country packages getting the extended length struts. Would be very interested in knowing why these trucks look to have so many random set ups in the suspension