I've got two vehicles that have the same issue. Both are 4x4's.
One is a '89 model the other a 88 model. Both trans have been overhauled in the past however I am unsure of when. The issue is when you start it, put it in gear and place it in the OD position, normally it would start out in 1st and so on. What both of these are doing is acting like they are going into OD, as you can give it a little pedal and it won't move. You can feel it trying to somewhat. However If I pull the shifter into 3rd, or the standard drive position and it goes into 1st gear like it's supposed to. Then I just move it up to the OD position and it stays in 1st gear and shifts out just like normal. OD seems fine going down the road as well. When I pull up to a stop sign, it goes back down to 1st gear as usual and shifts out fine again. But if I park it, shut it down, then get back in it and go 5 minutes later, again I have to repeat the process of pulling it back down to 3rd again to make it operate correctly. Any help on the subject is much appreciated.