Z71 drive line noise

[gcook]

Hi everyone. I've been lurking here a few days reading posts and decided to join. I have a 2002 Z71 with the push button electronic four wheel drive. I have a noise that sounds like a metal to metal rubbing sound that I hear when driving between buildings or guard rails etc. I jacked the rear wheels off the ground and ran the truck in 2HI mode and listened for the noise. The noise sounds as though it is coming from the front axle. In 2HI mode the front axle turns while the truck is moving. It's not driving anything, it is just being turned by a viscous clutch in the transfer case. This is what my dealer says. The dealer has heard the noise and says it is a normal sound of the auto four wheel drive trucks. The four wheelers with the stick in the floor do not do this because in 2 wheel mode the front axle is not being turned. Does anyone have this problem? Any info is appreciated.

 

thanks

 

gary

[snoman]

Hi everyone.    I've been lurking here a few days reading posts and decided to join.    I have a 2002 Z71 with the push button electronic four wheel drive.    I have a noise that sounds like a metal to metal rubbing sound that I hear when driving between buildings or guard rails etc.    I jacked the rear wheels off the ground and ran the truck in 2HI mode and listened for the noise.    The noise sounds as though it is coming from the front axle.    In 2HI mode the front axle turns while the truck is moving.    It's not driving anything, it is just being turned by a viscous clutch in the transfer case.    This is what my dealer says.      The dealer has heard the noise and says it is a normal sound of the auto four wheel drive trucks.    The four wheelers with the stick in the floor do not do this because in 2 wheel mode the front axle is not being turned.    Does anyone have this problem?    Any info is appreciated.

 

thanks

 

gary

 

<{POST_SNAPBACK}>

 

 

 

 

The front axle shafts always turn because there is nothing to disconnect them from the front wheels. The front drive shaft may turn some due to fluid shear in Tcase case but it should be very limited in 2wd and possible not at all when warmed up. If it (the front drive shaft) is always being drivin smartly, something is not disengaging in Tcase.