Finally Lifted!

I have the same exact vibration on decel at 25 mph and also around 65 mph on the highway. I only have a 1" block in the rear but am being told my pinion angle is out of spec. The stock leaf pack already came brand new with a small shim. So do I replace the flat 1" block with a 1 degree tapered block from low range off road or have the dealership install a 2 degree shim to replace the stock one? Thanks

 

I'm no expert, but I'd assume its a little more stable getting the tapered block...