i have a 94 gmc 1500 4x4. on my way back home from up north coming down I-75 i noticed that when i hit a bump it seemed like my truck swayed a little. thinking it was my tie rod ends i replaced all of them inner and outters and an alingnment. its still doing it. it also seems to shake/rattle the whole truck when i go down a very bumpy road and i dont feel any of this in the steering wheel at all so now im thinking its in the rear. looked under it and everything is good in the front from what i cant tell. no play in the ball joints at all, swaybar bushings look good, tie rod ends were all done and tires are all good. in the rear the leaf springs look good they are nice and curved with no sag in the *** end at all shocks seem kinda iffy but would they make my truck sway and viberate/ rattle over bumps? they dont seem that bad to me but i dont know what else it could be. i need to nip this in the butt this week as i plan to go up north for hunting on the 15th. any help would be awesome!
thanks,
chris

 

Bounce on the rear bumper enough to get the truck bouncing and then stop to see how long it takes for the truck to stop. It should not bounce more than a couple times before stopping completely. I would do it in the front as well. This will tell you if your shocks are bad. According to your testing I would be looking at the shocks too.

 

thanks for the info! what if just 1 shock is bad? would it make the truck swerve going over a bump? im gonna go test them right now. and if only one shock is bad would this test still work? thanks again,
chris

 

Yeah a bad shock can make a vehicle feel like alignment is bad over a rough road.