2000z71 1500 stuck in 4 high and makes loud tink on tight turns

Check the sensors on the transfer case and the transmission both. It's a pretty easy and cheap fix too by the way. Best thing to do is pull a network diagnostics test on the vehicle and it should tell you which sensor is bad.

check the vacuum lines to the actuator in the front wheels . check the actuator operation in the transfer case.

Hers a link that may help you on your way again :)
http://www.automotiveforums.com/t1061718-discuss2000_silverado_stuck_in_4wd__service_4wd_light_on.html

OK, you're looking at a CV Joint or Halfshaft that connects to the wheel in question.

try selecting from nutreul or less then 3km

Check the front wheel bearing assembleys.

The electrical switch going to the 4wd is bad more than likely. It would be the one under the truck

I had a problem with my tow/haul button not working. I came to find out that the gear shift had cut the wire running to the button in two. You may want to check that.

The problem is with the front actuator.Its flashing in the dash lights because is not functioning properly.Replace actuator and fix problem.Its a 4 or 3 wire screw in plug in front axle,,

I’m happy to assist further over the phone at https://www.6ya.com/expert/joe_a3369546f8067589

say cheese