No towing package, it's just a base 4.3 liter V6 air/auto. My thoughts too on why it sits high for heavier loads, the heaviest I carry are engines/transmissions, some plywood sheets, misc. junk., and it is still somewhat high, though most of time it is empty and it seems that if the Silverados sit fairly level and are good enough for most hauling duties, using the same parts on work truck would do the same here.
