I have a 94D1 and i was turning into the driveway just now and heard a clunk and now i have no gears nor park. Though when I lock the diffs I can move forward and back. Help! Thanks

 

Pretty much has to be a front endbroken axle, differential, or prop shaft.

 

Or the rear end.
Start the truck, put it in drive and look under the truck, if the rear axle is spinning and the truck isn't moving it will be the rear.
The good news is it will a cheaper repair then the tranny cause you can buy used parts.