So I got the RC 2.5 spring lift with zone nitro shocks. I couldn't figure out this vibration for the life of me. All driveshaft angles were correct (so I thought). Well I had a jks rear track bar in the garage for a couple months and never got around to putting it on. Well long story short I also had a slight squirm in the rear on acceleration from a stop too. So I didn't think the rear axle being of center would make that big of a difference. Boy was I wrong. Put the rear track bar on and centered the axle and bam; no more vibes or squirm. I ripped down the highway doing 85 mph for 25 miles and had no vibes or anyrhing. Now that the rears centered I'm investing in a front adjustable track bar from metalcloak too.