Installed 3 inch lift now i have a slight vibration

[14mins]

I just installed a unknown brand 3 inch lift in my truck. Now i have a slight vibration/drone that was not there before. I do not know if it is conincedence or not. It seems to be coming from the passenger front right or like right in the middle of the truck from behind where the tail of the tranmission would be. Truck has 110k miles on it. The lift kit came with a transmission spacer that i installed. ( about 1/2 inch thick). The truck does not appear to have slop in the drive line and of course it is dark outside now. Any common problems that result from adding a lift kit? The vibes disapear if coasting at 60 mph in nuetral, and does not seem noticeable under heavy acceleration. Any ideas? Thanks!

[Raul@Stealth Automotive]

what was used in the rear end for the lift if any?

sounds like driveline issue... prob your carrier bearing....

never heard of shimming the trans before.... usually its a carrier bearing drop kit to help the driveline issue....

i would say take it off and see if it goes away

[14mins]

Raul- I am an idiot, it was a spacer for the carrier bearing. They forgot to install it at the shop so i did 2 days later. Really not much chance in vibes. Maybe i need more drop or a new carrier bearing. 4 inch aluminum blocks were used in the rear. Thanks, Mark

[Vizsla]

Are the new rear blocks stacked under the factory block?

[DoubleDpsd]

I have the same vibration. Just left it. Is kinda annoying though.

[GGOODMAN]

one piece drive shaft stopped mine and my cousin's take off shutter problems.

[Vizsla]

Yeah that is where I was headed with the block question. I spent a good deal of time getting my driveline angles perfect(had to use tapered shims under leaf spring etc.), and still got vibrations. High quality aftermarket driveshaft and it runs as smooth as can be. Think the factory shafts are crap.