99 1500 front differential input shaft allways turns is this normal

help! front diff. is roaring always when moving . doesn't matter if in 2 or 4 wheel . can someone tell me if the input shaft between transfer case and diff. should turn all the time. mine does and I didn't know if this is right.
2 and 4 wheel works fine this in a push putton auto.shift
checked front greese and was black so something is not right
I check a 97 truck and the front input shaft only turn when in 4 wheel and is free when in 2 wheel.
This 99 truck has 2 wheel ,4 low and 4 high and auto 4 wheel push buttons maybe someone who has a 99 can check for me to see if theirs is free. I need to know if I have two problems. Can someone who has same truck check theirs to see if shaft between transfer case and front diff. turns all the time

thanks Robbie

pulled front ring and pinion and found pitted bearings and also found this post listed below when doing a search
thanks I found my answer

2000 silverado front driveshaft |
icerider []
AF Newbie
Joined: Aug 2004




08-23-2004, 01:13 PM 2000 silverado front driveshaft (Post #1)
My 2000 silverado z71 front drive shaft turns all the time even when it is not in 4wd. Is this normal? Does anyone have a solution?


simple_country_guy []
AF Regular



08-23-2004, 04:41 PM Normal (Post #2)
That is completely normal. You do not have lockouts on the front axle which means they stay connected at all times from wheel to differential to driveshaft. Your transfer case is where the driveshaft disconnects.

got to thinking about last post and thats not what mine does. My front drive shaft turns always with transfer case. I raised rear wheels and in 2wheel drive front shaft and ring and pinion spin with rear wheels ,only the axles are not locked in. anyone know anything else on this. It dosn't seem right to me. :banghead: