Vibes after rear shock install

Ok here is the issue guys...I have an 08 AC O/R. I recently did rear toytec 1.5 inch AAls. The install went smooth, but I also ordered a set of Fat bobs performance 8000 shocks with it. The AAL was installed first then I drove about 100 miles and then installed the shocks at a later date. My problem is after the AAL was installed with the factory shocks the truck drove well with no vibes. After I installed the performance 8000 shocks I am now experiencing some vibes at about 20 mph.

Has anyone experienced new vibrations after just replacing the factory shocks?

Thanks and BTW this place is awesome

 

So you are thinking me switching back to the stockers won't help me at all. When I compared these shocks side by side to the stock billies they were a good 1.5 inch longer if that would affect anything.

 

Shocks won't cause vibrations. Wheel balancing/ driveline angle will. Since you recently modified the rear leaf pack i'd start there, and any resulting geometry/ driveline angle changes. Also wheel balancing. It's likely coincidental that the vibes happened after the shock install.

 

They are definitely rear drive line vibes. I had new tires installed and balanced the day after I installed the AALs. I also had it aligned the same the day the new tires were installed. It was only after the shocks were installed that I started to experience the new vibrations. Them being coincidental would be just my luck.