I have a 99 jeep and if I put it in 4wd drive it makes a poping nose and the 4wd light stays on always and it’s a stick shift with the 4 cylinder.motor and I don’t know if the actuator is bad
You will need to put the Jeep up on a lift, engage 4x4 and listen for the noise. I believe the noise may be the transfercase chain jumping on the sprocket due to a stretched chain, but you won't know for sure until you can climb under the Jeep to locate the noise.
Slow down bud..dont buy anything yet..as stated you need to diagnose where the noise is coming from..you have relatives/friends that can help you? Have them listen while you try and replicate the noise and try to pinpoint it