1989 Ford F150 won't go in gear

[quote:ad93dab898="plsp"]Transmission problem
1989 Ford F150 V8 Four Wheel Drive Automatic 180000 miles
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If my truck is in 2 wheel drive it will not go in a foward gear. When foer 4 wheel drive is engaged it will take foward. Is the problem in my transfer case or my transmission?[/quote:ad93dab898]
check drive shaft
check rear end
check transfer case
if its the tranny then it will not work in any gear selection 2 or 4x4
check if the gear selector not rusty and working freely