Diff drop. Lift. ECGS. vibs. gone

Have a Toytec Boss 3" lift on my 16 OD DC, and had the diff drop installed. Have had it on there for about 31k miles. Everything was fine for the first 10k miles maybe, but then i started getting vibrations. Eventually got around getting the ECGS bushing installed at about 30k and vibes went away, but then quickly came back. Decided to remove the diff drop, and now ALL VIBES are gone, finally! The obvious conclusion is.... Don't put the diff drop in if you are lifted 3" or less. If you have it in, have the ECGS bushing, and still have vibes than i would take the diff drop out.