With a 2.5" kit you may not have an issue with the drive shaft at all. I had a 4" RE lift on my YJ and had no vibes with the stock shaft and no TC drop, I went ahead and did the SYE anyway, but I probably wouldn't have had to at 2.5 inches.
Member of JGW (Jeff's Gone Wheeling) and IndyORV
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Moab Trails I've done: Onion Creek, Long Canyon, Dome Plateau, Top of The World, Fins-N-Things, Poison Spider,
Golden Spike, Gold Bar Rim, Hell's Revenge, Baby Lion Back, Cliff Hanger, Moab Rim, Kane Creek Canyon, Strike Ravine
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