You will need either new shocks or shock extension adapters.
Given that you have a 2wd you have no shaft issues that I'm aware of at 2.5 to 3 inches of lift.
That said I went with a coil lift because I have 4wd, I do wheel and I wanted a different ride than a stock Jeep. I probably could have done a spacer lift and gotten similar results, but I do like the option to add a spacer if I add weight to the JKU later on in the form of bumpers.
Get the spacer lift. You wont be disappointed - youll have clearance enough for tires, keep your ride quality and be able to be lifted.
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