I have a 2018 F350 with the 6.2 gas engine and 6 speed auto. I pull a 9000lb travel trailer. In tow haul mode going down a hill the trans downshifts to lessen braking requirements. The problem is that it tends to “hold” the gear even when I try to speed up.
Our last trip I was going down a six percent grade and the next grade started immediately. I wanted to accelerate to gain momentum but the truck would not shift up until we were at the bottom of the grade.
i can hold a comfortable speed one to two gears higher when I put the truck on manual mode 4th when the computer wants 2 or 3.
the dealer can’t replicate because they don’t have a load.
any thoughts

 

Mine does something similar when using the cruise control, when descending a hill with cruise set, truck will downshift, if you turn off the cruise once it’s downshifted it will never shift back up, even once you’re on level ground. only workaround I found is resume the cruise and it shift back up by itself, or go to manual mode and shift up to 6, then go back to drive and it goes back to normal. Annoying for sure.

 

I just went through the same thing towing this weekend. Going down hill it dropped to 2nd (wasn't using cruise control) and the rev's were really winding up and wouldn't shift. I needed to gain some momentum for the up coming hill so I just slowing started giving it gas and just when I thought I better back off because it wasn't shifting, bingo! it shifted to 3rd then 4th. I played around doing that for the next few hills and that's the only way it would shift from engine braking in 2nd....go faster!

 

My truck does the same exact thing. There's no reason that it should downshift to 2nd. Then when I give it gas it takes a little longer to shift gears. My F150 that i traded wasn't this bad. I stopped using the Tow haul feature because of it. I only lock out 6th gear and go. I don't like my truck to be damn near redlined coming down a hill. Theres no reason for that. Maybe the dealers will come up with a PCM/TCM update.

 

Take the tow haul off and I bet it works.

 

This is all you have to do. Don't be afraid to push that long skinny pedal to the floor for a second to let the tranny know that you're ready to move. And don't worry about making that motor rev. If you can gain the speed in a lower gear by pulling 4 or 5k on the tach - do it. It's one less downshift it's going to have to do on the way back up the hill. Revs aren't going to hurt it at all. That's where the power is.

 

Same thing happened to me when in tow-haul. I don’t use it much anymore and manage my speed by locking out gears when climbing and descending hills. I can anticipate a lot quicker than the computer can. The computer only reacts to load & rpm and can’t see what is ahead. I do use tow-haul when starting from a dead stop and I want to get up to speed quickly without lugging. My last truck had a manual transmission and there are ways to make this trucks transmission work similar to manual trans. I only use cruise control on flat interstate speeds and don't use it with tow-haul on.

 

Put it in manual and shift yourself.

 

The shift strategies learn as you drive, refine shift points, and they are different in tow haul and depending on the load your under. Press the skinny peddle a bit more and it will shift up, but if you have cruise on or we’re engine braking, it does take a bit more, it’s trying to hold the gear to ensure the hold back is there in case you decide to take the foot off the go peddle. Tow haul generally holds a gear for an additional 200 rpm. It’s not much and the shift points are meant to handle load, such as towing. I use a combination of cruise +/- and downshifting to lock out gears and M mode when towing to suite the conditions and what I want to do. The more you do this the better you will be trained to shift, but I am not sure this allows the transmission module to learn as well either.

 

I tow often in the hills w/ 4.30....

I just switch tow/haul off when going downhill but trying to build momentum for an upcoming hill.
It does seem to get better with age.

 

No, that doesn't fix it. Once the transmission gets down to 3rd, turning off tow/haul doesn't release the transmission to shift up. The only way out of it is:
1. Increase the engine RPM significantly. It takes a LOT to get it to shift up.
2. Shift to M and make the shift happen with the button.

I have 13k on my truck and mine still does this. It has to be a programming problem in the transmission.

 

My truck does the same thing. Which is why I love the heated Raptor steering wheel I installed, complete with paddle shifters. When we're hauling/towing through mountain passes, I just drop the selector into Manual and drive the truck with the paddle shifters. It's AMAZINGLY AWESOME.