4 wheel drive / not engaging

Son has a 94 Ranger 4x4 with an automatic tranny. He used the 4 wheel drive during the last storm and all worked fine. He never read the manual and didn't know to turn off the 4x4 then back up a bit to disengage it.
Apparently the front end was pretty noisy for a few days before he told me about it (the noise). I told him to go in reverse to disengage it, and he said the nosie went away.
Today it snowed, he put it in wheel drive, and the transfer case engaged, but the front wheel don't engage, all you can here is it trying to engage (all that clacking). Is there a easy fix to this, or, an expensive one?

Thanks

May have to replace the automatic hubs for manual locking hubs. Mine went out last winter, so I replaced them with Superwinch manuals. Can't exactly remember the price, but I think they were around 200.00. However I'm much happier with them. Wasn't too hard to replace either.

I had the same problem with mine and i put on some WARN Manuals and they made a huge difference for around 200

My 99 ford ranger fades out of 4 wheel high drive after a minute or two of switching in. I have been to the ford dealers twice inwhich my transfer case has been replaced and the left and right hubs. I still have the same problem. They also said it is holding vacuum.

hey jackson 51. did your light on the dash go out when you said it faded in and out. how did you know it was fading out. just curious if i ever have this prob

i have a 99 ranger the transfercase engages but the wheels do not turn. the reason i know this is b/c when engaged the front drive line locks and when not engaged it spins freely. does anyone know what the problem may be? i replaced some vacuum line from the wheels to so some sort of diafram but i do not know if it was for the 4wd or not.
any ideas???