Lowered Square with Carrier Bearing

[Android04]

Good evening my Chevy Family.

So a couple years ago I lowered my 85' Dually with a 6/8 drop. It has always done decent around town and multiple road trips. But I've been chasing this vibration that I only seem to get at speeds above 50mph.

- It has been aligned (Twice)
- Does it stock wheels
- Does it with aftermarket wheels
- Does it with a load (Not as bad)
- Does it without a load.


So my thoughts are I'm getting drivetrain vibration at the carrier bearing.
This past weekend I stumbled upon a YouTube video where a guy who lowered a 3/4 Ton with a 2 piece drive shaft cut off the carrier bearing bracket to raise up the drive shaft. This apparently fix a similar issue, but I've not heard of that anywhere else.

Before I bust out the grinder and air chisel I was curious if most people do this to realign the drive train? It was not listed in any directions or anything I've read online. So any help would be great appreciated.

*Yes I want to convert to a one piece drive shaft but I'm waiting until I put my LS and 4L80 next winter.

[Dead Parrot]

There are other threads on similar vibration, including some on stock trucks. My 75 C10, stock setup, will do it sometimes. When it does it, it is normally starts above 65 and will rise and fall in intensity. It survived multiple tire changes, changing the rear wheel bearings, new u-joints, new carrier bearing.

About a year ago, I swapped out my 30 year old headers for a set of Hooker Manifolds. After seeing this thread, I can't remember the vibration happening after installing the new manifolds. Not ready to call the issue solved but I had long thought that it was possible the vibration was an interaction between the exhaust drone, the drive train and the natural frequency of the cab/body. Part of the problem is you sometimes don't notice that something is not happening, just when it does.

[SCOTI]

Both my squarebody dually & my '99 OBS CC SWB have had the carrier bearing raised to help w/driveline angles.

[Android04]

Originally Posted by SCOTI

Both my squarebody dually & my '99 OBS CC SWB have had the carrier bearing raised to help w/driveline angles.

Thank you sir!

I almost messaged you directly instead of making this thread. I appreciate the response and it looks like I will be cutting it out today and making a plate.

[SCOTI]

Originally Posted by Android04

Thank you sir!

I almost messaged you directly instead of making this thread. I appreciate the response and it looks like I will be cutting it out today and making a plate.

My OBS was raised 2" IIRC. The dually was raised a little more I recall but it was also custom vs the spacer Belltech sends as part of the flip 'kit'.