My 91 F-250 is stuck in park. It has the 5.8l engine with the E4OD transmission. I've been told that the neutral safety switch is bad, but when I look for parts, I find the part that is mounted on the side of the transmission, and a plunger type switch.

Question #1: Where is that switch located?
Question #2: Is there any way I can test the parts to see which (if either) is bad?
Question #3: Has anybody else experienced this problem and what did you do to fix it?

 

The MLPS (Manual Lever Position Switch) is located on the driver's side of the trans where the linkage goes into the trans. It has a plug on top with 5 or 6 wires. This will prevent your vehicle from starting if it is bad but shouldn't cause you to not be able to shift into or out of gear.

Find where the shifter cable goes from the steering column and down to the trans and make sure it is installed properly. Where the cable mounts on the steering column could have come off preventing you from being able to shift. Also, the problem could be caused by the column itself. You will have to do some digging to determine where it is hung up.

I think there is a test for the MPLS, this may help - https://www.ford-trucks.com/forums/2...-the-mlps.html

 

I'm not sure about the 91, but my 97 has the electric interlock where you have to have your foot on the brake to get it out of park. If yours has this check the brake lights, if they are not working check for a blown fuse or a bad or maladjusted brake light switch..

 

I have checked, and apparently there is no interlock on the '91, but the brake lights work fine.

I have taken the linkage apart underneath the truck and the shifter moves like it should.

 

This is a little out there, but I had a similar problem on my mom's car (a 97 cavalier). Since it was FWD, the NSS was right on top (saying that lightly meaning i didnt tear out half the engine to get to it), her car was stuck in drive, all we had to do was apply the parking brake, manually move the switch (which meant getting out of the car every time you needed to change the gear) and drove it to a salvage lot to grab a replacement.

Moral of the story, you can probably manually move the selector into drive and get it to the parts store, but for a RWD/4WD it's risky crawling under the car to put in and out of gear. But if it's your only ride you can move the switch by hand to put the truck in gear.

 

I had one of those on a 95 F250 I had...hate those things. It's controlled by a 2-wire plug that attaches to a motor on top of the steering column if you ever wanted to disconnect that.