Approximately 1.5 years ago while on a trip I experienced what felt and sounded like my transmission while in OD at 70 mph and with cruise control ON downshifting to third on slight inclines or when encountering an overpass, then shifting back into fourth. This was not consistent and sometimes was so very soft it was only felt when shifting back into fourth.

It became more frequent and started occuring at speeds as low as 35-40 and also when not in OD and with the cruise control OFF.

I took it to a Transmission shop and they recommended an overhaul.

9 days after the overhaul the problem reoccurred. I returned it to the shop and got it back a few days later with the request I return in 15 days for follow-up, the probelm did not reoccur until a day before I was to return it.

I took it back, they kept again for several days and called me to tell me that they could find no problems, that they had driven it 300+ miles without incident. I picked up the vehicle and the probelm seem to have been solved.

in the following months there were times it felt like the problem was reoccurring, but it was so soft as to be almost my imagination, and calls to the Transmission shop only got me more frustrated.

Shortly before the Transmission warranty was to expire the Transmission in OD and out of OD with Cruise control On and with it off in a 20 mile stretch of freeway a 65 mph shifted between 3rd & 4th a total of 35 times, on the trip back it did it once.

I took it to the shop on the way over the check engine light flash two or more times while it was shifting 4-3-4 and at the shop no one was available to go with me at that time and I had to leave it.

After several days the shop called said they could find no problems and the mgr went with me on a test drive. (Note: each time when I picked up the vehicle the radio clock time was correct, but the radio stations I had chosen had been replace by the radio presets)(also the fabric Washers behind the band adjustment nuts were squeezed out and I could see shiny new threads on the bolts).

The problem reocurred after about a week I took back to the shop and the mgr sent a mechanic with me and in a one mile stretch it shifted 3 times twice on level ground, the mechanic said the the T/C was dropping out of lock up. I was told to leave the vehicle and after a week the shop called said they had driven it 670 miles with no problems and they were taking it to the Ford Dealership for their input.

The Ford dealership could find no problems(also could find no computer codes in memory, even for the check engine lights) and in a test drive I took with the Dealership their were no shifting problems. in fact the Transmission sounded and felt diffrerent.

After about two weeks the problem came back even worse and I returned to the transmission shop and by the time they got through finding and hooking up a scanner and punching buttons on the scanner a TP122 code showed, then the scanner went blank and after that would only show a "computer not communicating" and during the test drive, the transmission again had no problems.

I attached a contact microphone to the transmission case just behind the bell housing and with my camcorder recorded the sound made by the transmission and the road conditions(flat or going up and incline). It recorded the normal shifts, the erratic shifting between 4-3-4 and also the latest hard shifts that shake the vehicle.

I call the shop and was told it did not matter if I had a recording, it did not prove anything and that my warranty was now expired.

The vehicle is not driven very day, more so on the weekends, and all of that in city, I'm afraid to take a trip in it.

Any suggestions

Also I am the original owner and I followed the service times including having the transmission filter and fluid changed.

I went to this chain Transmission shop because of good report from my son and for the same warranty it was $800 below the dealership $2500 quote.

When I picked up my Aerostar I left A 1978 chevy Nova for a transmission overhaul, and so far no problems but it gets driven less.

Sorry this is so long! I am really, really frustrated -- not the first time I have had problems with a repair shop over warranty repairs.

 

I have a 95 3.0 XLT Shorty that had (up until last week) the same problem for the past year or so. After reading much information in this forum, I patched a test light into the control line for the TCC lockup command signal. Sure enough, it wasn't shifting from 4-3-4 but was indeed the torque converter going in and out of lockup. I replaced the throttle position sensor a little over a week ago, and haven't had the problem since. I was also told several times I needed a new trans. But other than the slight perception of shifting everything else seemed fine.

At least worth checking. Although for the $23 I should have just replaced the TPS instead of jumping through hoops wiring a test light into the pass. compartment. Oh well, live and learn.

Best of luck to you. And thanks to everyone else on this forum for saving me another $2500!

 

I think Dave is right. What you think 4-3-4 shifts might be the Torque Converter going in and out of lockup. It could be the TPS or it could be the lockup solenoid in the transmission.

 

Thanks to Aerostar Dave -- I wish I had this info before I allowed the Transmission shop to overhaul my transmission(which did not fix the problem), I could have saved $1700.

I replaced my Throttle Positions Sensor $35.00 plus my labor and it fixed the problem. It not only stopped the shifting in and out of 4th gear OD, it also improved my engine power when entering the freeway.

My labor took nearly 5 hours as it turned out someone else(I'm the original owner) had attempted to remove the Throttle position sensor, and due to the Phillips head bolts being installed with something resembling Lock-Tite, had rounded out both bolt heads. I had to use wire cutters to gently cut apart the old sensor and then had to use vise-grips to remove the bolts and then had to go buy new bolts with hexagon heads.


Thanks again for the excellent advice.

 

Another victory for expert expert professional expert mechanics!!!

They got your money.

 

I'm glad this fixed your problem. But thanks goes to everyone on the forum. Their time in posting their experience was what solved your problem.

 

It is funny how things come together, The other night on my way home I felt the tranny "drop into 3rd" at 65 mph. it just shifted back and forth several times, barely noticable. I thought darn Transmission on the way out. This is good news! I will get a TPS and change it anyway, Too bad DaBar hadn't been so lucky. Do you suppose anyone at Ford is signed on here? Should be mandatory IMO.