I have a bit of head scratcher and was wondering if anyone has encountered this before. While in Drive, I can push lightly up on the gear shift lever and the truck will shift into Neutral. I can then lightly push down and it will shift back in to Drive. We're talking one finger gentle pressure...like checking if your steak is cooked. I can duplicate this almost consistently. The selector does not change its detent on the transmission. It's literally just the wiggle room in the shifter selection. On occasion, the truck will shift into Neutral while driving, even if I have not touched the shifter (again, the detent does not move). The overdrive switch functions as expected. No codes are coming up. I have adjusted the shift cable and checked the MLPS connection. Checked the linkage bolts under the steering column...everything seems fine. I'm guessing it is electrical, not mechanical, but stumped as to what other connections, apart from the OD switch, are related to the shift mechanism in the column. It's a 1992 F150 5.0L / EOD4 with almost 200,000 KM. Thanks!

 

HOW did you adjust the shifter cable? How did you check the MLPS? Which "linkage bolts" are you talking about? Read this page & each link on it:

(click this text)

 

Did you ever get this figured out? I’m having the same problem. Thanks

 

I got it about 99.9% fixed. TLDR: My guess is it was a wire shorting in the column. So electrical.

To be noted I did have the transmission flushed and checked for debris and examined the linkage bolts for play (not the problem). The issue started with a frayed shifter cable that eventually jammed. I replaced the cable and adjusted it according to the above link. I also reset the gear indicator as per above as well. The symptoms still persisted. I then changed the MAP sensor and fitted a new Neutral Safety Switch (MLPS I think) located on the transmission. Adjusted the MLPS according to directions. These senors can be related to the issue, according to online information. The 'neutral shifting' issue persisted, but it was a little different, as in earlier in the rev range. No clue why. I then pulled the column down and went over each wire to check for cracks, shorts, binding etc. One wire that went over top of the shifter mechanism was stretched and kinked (can't remember the color). I smoothed it out, didn't seem broken inside the insulation, so I put it back together, readjusted the shift indicator position again (as per above). That seemed to solve the problem and the issue has not reoccurred. I also put the OEM MAP back on. The only remaining issue is that when it's really cold the shifter needle will 'float' a bit when I move the lever...if that makes any sense The detents engage no problem. Once the cabin is warm it doesn't happen. So something needs a bit more adjustment or the little plastic shifter pointer mechanism (tech term) and its thin cable needs replacing. I'll find and replace that column wire when I'm back in the column just to be sure. But it works for now. Hope this helps. I can appreciate the frustration in trying to figure this out.

 

Thanks for the info! It set me on the right track! I think the shift linkage is misaligned. I replaced the sensors you mentioned and saw some improvement. I’ll post more in a few days. Thanks again!

 

Loose shift linkage is a known problem. The bolts can even back out completely in some case. For what it's worth, you may want to check the wiring harness that runs under the transmission along the mount. Rabbits had munched away the outer insulation on mine, fortunately not the wires themselves. Dirt and moisture got in there before I noticed and wrapped it up again. It's a pretty exposed location, not all sure what is connected down there, but worth checking either way. Good luck tracking down the issue!

 

Before I go disassembling things, do you know if slightly rotating the MLPS might correct the truck not knowing if it is in drive vs neutral, or would I be better off trying to adjust the actual shift linkage? I realized after the previously posted repairs that the truck has never been in overdrive, what a difference! I’m having issues posting from my current location, otherwise I would provide more info. I get home tomorrow.

 

I really don't know about the MLPS. There's really only one way to put it on and it has 'line up' marks. It can be tweaked if there is a no start situation. At this point it might be worth reading the codes. Although the shifting issue doesn't always throw a code. There is some more discussion on the subject here: E40D tranny going into "neutral" while driving and here: how to tell if a mlps sensor is going bad?? Seems the culprit of the 'neutral shifting' symptoms is electrical in most cases.