Hi fellas, I'm throwing this on here for a friend of mine. I never did address this issue after I sold him my old Rubi. The Jeep originally had 3 inch lift springs, with a 1 inch bl/mml. They were removed and replaced with a 2 inch budged boost. After the swap, there was the tiniest bit of drive line vibe, and for the life of me I cant tell him why. Everything was installed clean, and the mml/BL was already in there..I'd appreciate any info.