Here was my experience with that...
Here was my experience with that. My '93 Explorer XLT 2x4 was doing the classic no shift from 1st to 2nd when cold (70k org.mi. believe of not) And thank god for these great forums. This info saves me mega bucks since I can still do this work myself (age 56, ha!) If it'll help,I'll outline a what it took. Got the front end on blocks,rear up on jack stands so you can turn drive shaft/wheels. Put scissors jack under rear of trans pan cuz when you remove cross member, keeps it from falling on your head. Remove drive shaft:you need a 3/8 dr.12 pt socket to remove 4 differential flange bolts.Get ready for the factory loctite red thread locker. They're tough to back out. Had to cut the end off a 12mm 12pt wrench so I could put a cheater pipe on it. This is 1st time to rotate drive shaft to allow access to these bolts with modified tool. The second time will be in assy to torque these 12mm bolts. Had to put it in park 4 dif times for this. Slide drive shaft out of trans, get a pan, some fluid comes out. Remove speedo and hang it on the plastic loop provided (maybe you'll see it, looks like it was left there just for that purpose). Remove cross member (make sure you have a 18mm socket) Had to remove some kind of anti vibration piece on ext housing, has 3 bolts. Remove housing bolts/nuts. Two are studs on left side. Okay, here's where the ATF starts flowing out when housing comes lose (needed the pan!). All in all, I lost about a 1 & 1/2qts.of fluid. Housing comes off, there you'll see the what I call the down shift governor. There's a piston valve sticking out of the governor housing and yes it was stuck when I tried to push it down with my finger (great news here because that tells what the problem is and now it can be fixed) So, remove the two bolts to gov. You'll have to keep output shaft from rotating to the left. I used a plastic handle from an allen wrench,stuck it in the park detent spaces, but use whatever works. I decided to refurbish this since I didn't see them available on net. Looks to me like another Ford flaw here because the housing is soft aluminum and the piston is hard steel with sharp edges on it which look like they gouged into the housing over time and stuck. Got my 600 & 1200 grit wet/dry & crocus cloth on piston & housing.Had to slightly remove sharp edges on piston and smooth out gouges in gov housing. To get it right it took me about 1 1/2 hrs.The only part I had to buy was ext. housing gasket. Already had Explorer shop manual for torque specs and some hints, but not many. Assy is reverse process, did the torquing to spec, added my Mobil 1 ATF, put vehicle on floor, let idle few min to circ fluid. This does the TRICK!
Trans shifts quite well, thank very much! I hope this helps someone do this repair, I'm not an expert mechanic by any means. Just a guy with a two car garage and some tools. Hey, you can do this!
