ok, i have an 98 expy, i can put it into all wheel drive, but when i move selector to 4H or 4L i just here a clicking sound for a second or two, then nothing, and the selector light won't come on, i know the light works, and the 4wheel drive did until it started snowing and icing here,, any thoughts!!!

 

Mine goes through the same crap. The light will blink and I'll hear the click several times, but the 4x4 ends up coming on. And I hope when your trying to shift into 4L that you are indeed in nuetral

 

In most of my trucks I have had to run it through 4hi and lo about once a month to keep things from locking up.