Hi all,

My 2013 F250 (76,000 miles - 6 speed 6R140 transmission) is experiencing a transmission problem the Ford service writer says he has never heard of before. After searching the internet for a month, and taking the truck to a trusted transmission specialist and a shop that specializes in electronic problems, I am beginning to believe him.

I have been driving the same relatively flat North Texas road with the same travel trailer (around 6,500 lbs - truck rated at 12,500 lbs) for 4 years now with no issues. Now, and ONLY when I am towing, regardless of whether I am in tow or regular mode, the transmission will down shift randomly. For example (and I made a video of the instrument panel to show the repair technicians), I was doing 60mph on a flat road in 5th gear and the transmission shifted into 3rd gear and revved up from 1,800 to 4,000 rpm. I let off the gas slightly and after about 30 seconds it climbed back to 5th. If I tried to even slightly accelerate, it would drop as low as 2nd and up to 5,000 rpm.

I took the trailer out again last week and the same problem, going and coming.

If I put it in manual mode, I don't have the problem, but I am constantly having to remember to shift up and down.

The transmission fluid level and color is good, the transmission temp has never risen when doing this (below the middle of the gauge), no check engine codes, no flashing tow mode light/TCM codes. There are no noises other than the whine of an engine getting close to the 6,000 rpm redline. I checked for a rolling resistance problem with the trailer, but the brake hubs and axles were cool to the touch after 40 miles of rolling. I jacked up each axle of the trailer and spun the tires freely.

Without a load it is absolutely perfect, which of course is the only time that a technician has examined it and said nothing is wrong.

The technician who specializes in electrical problems says, based on the video, it looks like the computer is telling the transmission to shift at odd times, but he doesn't know why it would not when it is not under a towing load. The transmission technician said the transmission appears mechanically fine. The dealer service writer says bring the truck and my check book in without offering any other insight!

Has ANYONE else had this problem?? Unfortunately, the video is mp4, which can't be uploaded here.

Your help is greatly appreciated!

 

Are you in tow/haul mode when this happens?

 

Does it in tow/haul and regular mode, with cruise on or off. Here is a link to the utube video of the instrument panel

 

It may not be related to the load of the trailer but perhaps it's an issue between the electrical connection of the trailer and the truck. That would really be the only way the truck would "know" there is a trailer attached. This is an unsafe suggestion, but if it were me, I would find a road with little or no traffic and tow the trailer with the electrical connection disconnected and see if it still shifts erratically. I'm not really sure what to do next if the problem goes away, but at least it would have some sort of tangible cause.

 

These trucks have a sensor pack that can tell the control module if the vehicle is climbing a hill. On ascent, it will downshift quicker and hold the lower gear a lot longer. Maybe your pitch sensor needs calibrated.

 

 

All I am hearing is your radiator fan.

 

Never thought about it being a radiator fan. That would be a good thing in that it has nothing to do with the transmission. I can live with that.:-).

 

Ya I think the noise is just the fan spinning extremely fast.

 

As an update, my fuel pump went out completely two days after the PCM reprogramming. The technician is thinking that its intermittent failure may have been contributing to the downshifting to an inappropriately low gear as the computer was trying to compensate for loss of power. That may be why I am hearing sounds that I normally would not hear when I tow..I don't usually do 60mph in 2 and 3rd gear. Sounds logical, but a painfully expensive repair.

 

That makes sense, but was the fuel filter plugged?

 

I would agree that sounds like the cooling fan. After watching your video your coolant needle is fluctuating quite a bit. Maybe that's why the fan is running so high. I tow a travel trailer with a similar weight and I've never heard my fan kick in. I drive similar flat roads as you do. Have you checked your coolant concentration lately?

Edit: just noticed, looks like you have the 6.2 not the 6.7 so YMMV.