Ok so this may oin the wrong spot but here goes, I drive a tractor trailer for a living and my tractor will build full boost even at low rpms, my dually will not. if im pulling a hill and loaded down it will just lug along at about 14-17 psi until the rpms start to gain then it will run to max psi. even when floored with the tc locked unless i drop below 55 mph then it down shifts and builds max psi, is something wrong or is it just and auto tranny