2000 4x4 rearend/tranny and or brake problems?

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

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


bouncing would be the shocks ...take out the tranny mount and inspect for separation ...

when checking the U joints,,, both rear wheels OFF the ground place tranny in neutral and rotate drive shafts as you check for any defects....


4wd with a v6....this must be a slow vehicle ...I never thought that this was oem produced....

bouncing would be the shocks ...take out the tranny mount and inspect for separation ...

when checking the U joints,,, both rear wheels OFF the ground place tranny in neutral and rotate drive shafts as you check for any defects....


4wd with a v6....this must be a slow vehicle ...I never thought that this was oem produced....
actually its not bad its actually got some balls and ive seen a few 4x4's with the v6. dont get me wrong it is a dog compared to my 82 c10, but the 82 was becoming too much of a problem a dime here a nickle there which is expected of a 26 year old truck!

Replace your throttle positioning sensor this will take car of the truck bogging at 45 and the truck acting like it does not no what gear to be in it cost about 35 dollar at any auto parts store there are two different ones for that truck so remove the old one first