Welcome to the forum!!!
Driveline issue and since it happens in 4 wheel you may have something in the T-Case or front axle happening. U-joints, flange or yoke loose, T-Case issue old loose chain, or the worst a differential going bad.
89YJ 2.5L TBI, AX-5, NP231 SYE, Ford 8.8, Yukon Grizzly, Tom Woods Shaft, 33" BFG T/As, 4" lift, Warn VR10000s.
AF Jeep Club Tail #184