hi everyone i have a 00' 4wd silverado with the 4.3v6 auto its got 100,000 miles and has a 2" skyjacker lift on 17 inch american racing rims. ive got a few problems: When i come to a complete stop and then accelerate i can feel something in the rear giving, it dosent make a noise its just like the rear of the truck drops alittle before it goes(springs)? i thougt it might be the bump clunk prob but i cant find much on this topic. also when im cruising at speeds of 40-55 and hold my foot in the same spot for cruising the truck bogs it seems like it should be in a lower gear and is struggling at a higher one if i step on it harder it will finally drop down and go this is worse on inclines. and i noticed that when i come to a stop and then accelerate my t-case shifter moves back like an inch then returns to its original position when i reach the disired speed,Is this normal? i cralled under the truck everything is good and tight (u-joint,shacles,rearend mounting points,brakes,etc),But i did notice that when rocking the truck in park the rear moves up and down like crazy,not because anything is loose but maybe because of the springs. thers only 3 leaves 2 large ones and a smaller one on the bottom,are they to weak? I was also wondering how i can tell if my tranny mount is bad because if i gun it i can feel a bump under the trany tunnel (trans hitting floor maybe?0im new to the site and im hoping some body can help me out thanks Jeromy