axle problems?

[low and loud]

ok when i go down the road with my truck it starts to vibrate at about 45mph but not bad until you let off the gas then it feels like the back end of the truck is moving to one side and then when you give it a little gas it goes back to the other side and its really moving alot. is that something to do with the axle or do i have some other problems that i need to address? i dont know what could be causing this but i know that it doesnt feel very good when your cruising down the road.

[Jake Nac]

Check u-joints and rear yoke.

[DROPPEDGMC]

i'd say check the u-joints:cool:

[firehawkclone]

I say start checking everthing,like u joint,yoke,springs,u bolts ect.......

[XxInFaxX]

start with the u-joints

[low and loud]

the u-joints can make the back end walk around like that? i realize that u-joints will cause vibrations but thats not my major problem.