1997 chevy k1500 4x4 Makes a weird noise when in 2wheel and goes away when in 4 weel drive. Noise is in right front. transfer case location.

Hi Alex W, chevy k1500 A/T box? 4L80? sure 4wd,
get it checked out in a real shop?
we can not do the checks here, nor hear it
we would use and electronics, stethoscope to find
it zero risk to human body.
not told you, will it grind, parked , and makes noise
in all PRNDL selections, 2H mode.
or shift to 4wd neutral does it make noise"
my guess is only moving it makes noise!?
if yes tests can be dangerous to the tech and others.
is transfer case NP208 transfer case?
see this N here/
we can shift to N to see of noise ends.
a loose chain in the box below can make noise for sure using 4wd on dry pavement.

NI is for towing mode, see in the users guide. yours.

Transfer case is bad. My first guess. If the transmission were bad it wouldn't move at any position. Is there any noise? You have 4 possibilities, Front and rear differentials, transfer case, and the transmission.

You need to have the gears and bearings checked in the front diff .

Shift the transfer case to N while it is making the noise. If the noise goes away the transfer case is the culprit.

Harmonic balancer.

this could be a problem with the transfer case i had a 98 chevy blazer 4x4 that did the same thing till i replaced the transfer case

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.

I have the same problem with my 94 explorer with a manual transmission, Just replaced the trans a month ago because of gear failure and now It's slipping out of gear when the engine isn't under load aka Coasting, was Told By a Really good Trans Guy that this is a failure in the Linkage in the transfer case am about to tear into mine tho It's way over my technical ability but will repost here after I get it torn apart with potential prices for worn parts for the do it yourselfer, And Has to be the issue I hope because the gears in the transmission are in pristine condition the other reason for suspecting the transfer case is that when my trans is slipping and making that weird Rattle Clatter sound coming from the trans if I put it in 4x4 low it drives great even tho the front wheels aren't pulling since I have the front drive shaft off at the moment,, Well Here goes Nothing Wish me luck on this teardown gonna need it..

mine did the samething you have check if there is any transmission fluid in your transfer case. because i didn't and i put more in and the grinding went away.

i had the same problem.. it is the vacuum switch on the transfer case. the switch is stuck open and supplying vacuum to the vacuum diaphram under the battery box. the switch is located on the upper side of the transfer case ( not the front differential) which is located driver side of the transmission. the switch cost me about $25.00. I replaced it myself. if you do your own mechanical work you can get it done just be patient.