4 low stopped working

[fidia11]

So I got my tahoe out this morning and had to lock it in to 4 low just to move. When I got out on the road I was traveling about 20mph when there was a crunching grinding noise, it sounded like the front driver side wheel making the noise...then a pop and the truck disengaged the
drive line all together. I pulled it into 4 high and everything seemed to work. It seemed like the 4 low went out but the 4 high still works. I am new to the 4x4 end of things, any suggestions on where to start. My tahoe its a1995 tahoe 4x4 2 door

 

[SunlitComet]

It sounds like specificly your planetary gearset in your tranfer case broke.
It provides the gear reduction for 4lo. No choice but to tear it down for inspection.

 

[fidia11]

All of the noise I was hearing was definately coming from the front driver side
wheel. Any chance this could be a front differential problem....I havent' proved it yet but it acted like I only had 3 wheels spinning when I went back into 4 high. And I'm in no hurry to pull the transfer case out (mabey this spring). Will it hurt the transfer case more if I keep driving it in 2wd???

 

[SunlitComet]

If your indicator 4wd indicator light comes on after switching to 4hi then rest assured your front differential link is locked assuming nothing in there is broken. That would not cause a total power disconnect like you described. If vehicle drive in such and you try 4lo with 4wd light on but no movement at all for entire vehicle but fine in 2wd and for 4hi it is most likey the gearset. 2wd or 4hi should be fine but avoid any range shift into 4lo. Hope for the best. Any new info pass it on.

 

[fidia11]

I appreciate all the help sunlitcomet. I'll be sure to post back if and when I tear into it.

 

[BigDaddy13440]

This sounds exactly like what mine did, except I don't have 4wd at all....