4wd random grind! help!

[motorheadwannab]

So here I am drivin from AZ to Cali i'm coming down a hill so i let off the gas, as I do i feel my car shudder and my 4wd light comes on! I start freakin out as I am going about 85mph I grab the 4wd selecter and pull it back as hard as I can but it is still grinding away. I slow down and everything goes away, light goes off no grind nothing. I pull off and go through all the 4wd in and outs but everything seems fine! I got back on the road and it did it again for no reason it actually even managed to get into 4wd once...not good. If I am driving too fast and push the 4wd button it beeps saying no no so i don't get it! I crawled under and everything LOOKs fine , no broken wires etc, What could be wrong?? I am scared to drive it! I know it was the 4wd grinding as i could feel it in the selecter and definitely feel it in my seat! Help me if you can! Oh, its a '96 4runner limited 3.4 no diff lock
thanks

 

[animator]

Smartest thing you can do in that situation is throw the transmission into neutral and coast onto the shoulder/emergency lane as safely as possible.

 

[motorheadwannab]

Ya that is the best thing to do but doesn't anyone have an idea what it could be? I need to drive back to AZ this friday and i'd like not to destroy by truck...anyone?

 

[4reak]

my gears have grinded before too...it doesnt sound as intense as your situation, but it did. i had no clue what it was...i just got over it since it wasnt that bad. but i guess i should have it checked out. it happened when i was breaking and i hit a clump of ice in the road, i could feel and hear the gears grinding, and there was a lot of vibrations in the brake pedal