Hello all, Chris here from the island of Long Island NY. Been lurking for a while and have learned much from the trials and tribulations you've all been through with these Fords. This is truly an awesome opportunity for those of us that appreciate the knowledge you all have.

I own a 90 7.3 with low original miles and a twice rebuilt E40D that has been "Neutralizing" ????? on occasion for 2 years. Of course when it goes to the tranny guy, it performs well every time.

Just did a business trip looking for work, signing out of state books and went through 7 states, ending up in Maine, near Bangor. tranny acted up on occasion and then would clear up. On the day we were to leave Maine, we pulled out of the driveway and all hell broke loose. Took 1 hour to LIMP 10 miles. We got back and found a reliable tranny shop through a friend of a friend. Took over 90 minutes to limp to him. He dropped what he was doing and took it out,,,,,,,,,,,,,No Problem !!! ?????

To cut my rambling short, he had it almost every day for 5 days and said the tranny was fine, and he believed it to be electronic. He DID NOT want to rape the innocent unsuspecting Long Islanders and was one of the best professionals we've ever dealt with in over 40 years.

He replaced the speed sensor at the rear end.

Unfortunately after a weeks delay we had to gamble on the long trip back.
It burped on occasion but ran 95% down to southern CT,,,then it raised hell all the way home. it has been a nightmare ever since, every day, non stop.
Took it to our guy today. He took it out and it finally acted up, shifting at over 2500rpm at below 50mph speeds. Seemed to meutrlalize from 1700 up. It did it at 35mph and then 45, then 40, then 55. Got back, checked fluid, OK, and scheduled it in for next Tuesday.

I had this rebuilt twice. Now I believe that that was a costly mistake. I believe Mike, the guy from Holden Maine was on the right track but the NY guys seem clueless and would rather sell the rebuilt unit than try and isolate the problem and correct it.

Sorry for the War and Peace intro. but losing my mind over this.


Chris

 

my fellow Mainer was correct.
it is electrical,but it's not the VSS.your issue is a failed MLPS.
you can fix it yourself.it's likely been updated to the latter MLPS already since its been rebuilt (and like you say,probably needlessly)
forget the amazon part finder thing,this IS the updated MLPS you'll need:
Amazon.com: Motorcraft SW5978 Neutral Safety Switch: Automotive

that's a quality one,and comes with instructions to re-pin if you do need to.
this sensor is located on the drivers side of the trans,that the shift lever hooks to.
unbolt that center nut (15 mm) then the two sensor bolts (8 mm) and slide it off.
carefully unplug the sensor and try plugging in the new sensor (SW5978) if it plugs in,then your good to go.forget the instructions in the box,if it doesn't then follow the instructions.
line up the little marks on the sensor,and slide it back on (edit: with trans shifted into N before you took the 15 mm nut off,and wheels chocked+ e-brake set) bolt it all back up,and you should be good to go.

if you'd rather,just take it to the dealer (or local trusted mechanic with part in hand with instructions from box) and tell them you'd like it installed.

hope you enjoyed your stay in vacationland.come on back up next year!

 

Thanks for the reply and the info. Very, very much appreciated. I will be doing this hopefully tomorrow if the part is readily available.
BTW Mainers, in my humble opinion, are stand up people, no matter what, and to be honest, I'm glad I got to meet another stand up guy in Maine. Mike is gonna get my E4 from an 88 that I have collecting dust and I'm pretty certain he'll build it the way it needs to be.
Thanks again FORDF250HDXLT. I will repost on how this works out.



Have friends up there in the north east so we're up that way as often as we can sneak away. Great country !!!! We'll be back in the fall.

 

Also having electrical problems with the tranny !! The mechanic says I need to get a new TCM !!! Where? Allready got screwd by someone in another blog !!sent him the money and never got anything !!!

 

Hey you mentioned that he might have been updated already. If it hasnt is it still the same part?

 

you'll want Motorcraft SW5978 either way.
if it hasn't been re-pinned to work yet (unlikely,if the truck has a few miles on it) then it won't plug in.you'll simply follow the instructions on how to do so that comes with the part.
if it has already been re-pinned then the part will simply plug in without any modifications required.


oddly,they still sell the old MLPS too.it was revised in '95,and ford recommends updating to the latter style plug as its better at keeping moisture/corrosion out than previous years.the instruction sheet will be easy to follow for your local mechanic (or yourself.)
inform your mechanic to unplug the solenoid pack plug on the passenger side,and unclip the whole harness so it comes down around the back side along with the MLPS connector,so it's all down where it's easy to work on.the job is MUCH easier if you do so.......i unwisely didn't do so and it was a bear lol!

 

Wow, lost all tranny function very quickly under no load, no debris in pan - and now, no movement in any gear. Could this be as simple as a bad TMS or MPLS? Thanks!

 

Ooops,meant MLPS

 

No you might of lost the converter or the pump if it wont move in any gear its basically done, Pull off one of the cooler lines and start the truck for a few seconds and see if it pumps fluid.