Won't go into 4x4 hi range

[hidesherheart]

Hi guys!
I have a 99, 7.3L with 120,000 miles and it won't go into 4WD Hi, it will go into low range with no problem. It of course has the switch on the dash. I am assuming its electrical (I know, its dangerous to assume, lol) Any thoughts? I love my truck!
Be gentle please, I am a woman and don't pretend to know alot about the mechanics, I am a nurse, and work with the developmentally disabled, now thats my field of expertise, lol.

I appreciate your help! Twice now I have come here for help and you guys have been spot on each time, so much appreciated. Its helpful in that when I take it to be repaired that I know a little about what to expect.

Thanks again.

[elibenson]

I would say that if the low range 4x4 works, then there is nothing wrong with the transfer case. If it were my truck, I would start looking at the dash board switch. I've never had any problems with any of my trucks (6 of them so far), past or present. But if I did have that problem, I would start at the easiest part, the switch.

Maybe some one will give you a better answer.

[adfields]

The gear motor on the back of your T-case, you can replace it or maybe fix it. It has contacts on the gears so when the dash switch is set to 4H it moves half way. Put the switch in 4L and it uses a different set of contacts to move the gears all the way. Open it up and check these contacts as they may only need cleaning or the 2H wire soldered back on.