Been driving my 91 F150 for about a year with no sign of problems. Yesterday as I drove under an overpass I heard all I can describe as a big can full of marbles being shook. as I cleared it I didn't hear it so I thought it was work being done overhead. About 2 miles done the road the truck just races and no go. Well it's 100 degrees and I roll to a stop miles from nowhere. I figure I have nothing to lose so "Pray Hard" and put it in 4low, it's goes but I have to hold in in 4 low while nursing it at 2500 rpm doing 30 through every back route I know. I'm thinking I blew the High gear in the case, but I have zero experience in this situation. Any thoughts would be greatly appreciated.
Fred

 

With 2hi selected and the trans in Park can you push the truck forward and back? With 4lo selected and trans in park does it push forward or back?

 

Will try that, It's 98 degrees today, so I will probably wait till the sun gets a little lower. I haven't looked at anything yet. Thanks, I will post results

 

Tried it and that is exactly what is happening will roll in 2 hi 4 hi, locks up in 4low (no roll)

 

Then you either need to rebuild the transfer case or get a junk yard one. They are not difficult to replace.

 

Thanks, That was my first thought, but didn't know enough about the symptoms to plow into that job without being sure I was attacking the correct problem . And looking at the way you have helped others you HAVE the knowledge. Thanks again,
Fred

 

Just 2cents to add...

Try your local craigslist: los angeles classifieds for jobs, apartments, personals, for sale, services, community, and events or even better crazedlist.org : search craigslist like a madman will allow you to search several areas at the same time for a t-case. I can also send you the entire ford rebuild instructions if you want them... Email me at nstueve@gmail.com for them!