2000 Chevy Silverado 1500 4 wheel drive makes a scraping noise when turning

This video should help. It's a 2000 Silverado but is probably the same as yours.
2000 Chevy Silverado 1500 front brake pads rotors replace

check the adjustment of the parking brake shoes, most people remove them completely because of the constant noise that they make

because when engaging low range on 4 wheel drive vehicle you should be standing still.

Good Evening, those noises can be annoying and sometimes hard to find. However it sounds like you have a front hub assembly going bad. Usually the noise goes away when you veer one direction or the other. I have heard some transfer case noises but they usually do not go away on turns. Check those front hub-wheel bearing assemblies and see what you come up with. Hope this points you in the right direction.

The electrical wire came loose from the back of my 2H, had to take the panel off and re-soder it. Works fine now.

Transfer case would only be if you are in 4 wheel drive. this sounds like a rear end or u joint issues. Get under the truck and grab the drive line, if you are able to turn it more then a 1/4 inch each way bad u joints. If not then check the rear end.

I am by no means an expert but I had the same issue with my 2000 chevy 1500. I bought a new 4x4 switch from the dealer for about $70; it just pops out and back in; it completely fixed the problem including the fact that it would not kick out of 4 wheel drive. Apparently the switch is a very common problem with this make and model.

it is almost impossible to solve without hearing it in person, but some things to check are the front brakes, front wheel bearings, tires, and loose suspension parts.

you may have a bad transfer case

the shifter accuator or the wires going to it on the transfercase..gl