Help with my suburban please

[Rattler]

I believe it's the actuator as well. Especially if your 4wd indicator light is acting up. You could have a worn out return spring causing the collar to partially disengage and making all that noise.

First thing I would do next is Jack up the front passenger side and try and spin the tire. With the actuator in normal 2wd mode you should be able to spin the tire since the collar would be disengaging the outer axle from the inner. If the tire spins and the noise is present then you definitely have a problem with your actuator or collar retraction. Make sure when you are turning the tire that the drive shaft is not turning. If the drive shaft is turning then your actuator is engaged when it shouldn't be.