Bad vibration??

I've got 2 wine/vibrations that feel like its coming from the driveshaft/tranny <img src="{SMILIES_PATH}/icon_mad.gif" alt=":x" title="Mad" /><!-- s:x -->
1st one is when i'm pulling a hill and have pressure on the drivetrain...pretty loud inside the cab and it sounds/feels like it coming from the back of the truck.

2nd one is when i let off the gas...more of a wine and that one feels like its right underneath the tranny tunnel.

I have replaced the carrier bearing and didnt do much, if anything
It's got a 5/7 drop with a flip kit and 2600 bags behind the rear axle

ANY IDEAS/RECOMMENDATIONS??

sounds like a pinon bearing to me man, could be a u joint but they usually dont last long after they start makin noise so if its been doin it for a while i dont think thats it, also before you go tearin into it change to different rear end lube, like royal purple and see if that changes any thing. If it does it could be in the gear set

THANXX MAN!! I'LL LOOK AT IT THIS WEEKEND

check to see if the rear part of the 2 piece drive shaft is pushed into the front shaft too far. i have seen this several time when running the flip kit. the axle relocators have 2 holes drilled in them, and if you have it in the front holes it moves the rearend forward too much. let us know the outcome. later, brian

ok, i got under it and didnt see anything wrong with the driveshaft, that i could tell anyway

And forgive my ignorance but, where are these axle relocators you speak of?

See the two pieces in the center? They fit btw the leaf spring and the axle after you flip them.

Has it always had the vibration? Or just started lately or after the lowering?

ok cool! I'll have to get back under there.

It didnt always have it. I replaced the center support bearing and was told the u joint were in good shape too.

hmmm. My 90 does this exact thing too, I haven't attempted to fix it yet. The whine I get will stop if I let up on the accelerator when I hear it.

MY truck is doing the same thing... it feels like the front... i can feel it in the pedles and everyhting. it shakes so bad could shake your kidnes out lmao. any help would be awsome! oh it only really vibrates around 80Km+

the pinion angle on these trucks are critical! does all of your trucks still vibrate when loaded down? when rolling slow,like approaching a stop sign, do any of you feel a slight poping? when the pinion angle is off, which occurs with a flip kit, you must space up the transmission and carrier bearing until you get the angle correct.