Right. Most of us complaining are driving the 6.7L, which is not normally considered a high revving engine, which is why there is concern for having to add 1500 RPM to get an upshift.

 

The engine management software will keep you from damaging your PSD. You're not going to over-rev it or overheat it.

Don't baby your truck. Work it hard.

 

The PCM will not allow the engine to overspeed.

 

I find it not too bad on gradual descents but a PITA on steeper/slow roads. One of my fishing spots has a long, slow, bumpy road out with some steep sections.
I just put in manual and shift as needed. Seems to work well for me.

 

When pulling my 5th wheel on steep downgrades, I also use the manual mode to save the tranny from downshifting when I need to touch the brakes to slow down on sharp mountain curves.

When just locking out gears, the truck is hesitant to upshift on steep down hills when I reengage the next upshift gear. If that happens I will temporarily turn the engine brake to let the tranny upshift without having to wind out the engine.

(Post edited)

 

If you put the transmission in Manual mode it will upshift. If you leave it in Drive, that's when it fails to upshift. Locking out gears isn't the same as shifting to Manual mode.

 

Oops, my bad. You are correct. I was thinking about locking out gears. And that is another reason to use the manual mode.

I will edit my post.

Thank you.

 

I noticed the same thing with my 2017 Diesel.
Hitting the gas peddle will cause it to up shift but I found that I like the full manual mode better.
I pull a 14000 toy hauler and I find it gives me better control coming down hill.

 

Manual mode it is then! Forgot I had that ‘

 

Another vote for manual mode downhill. There are some instances where we are smarter than the algorithm.

 

Here too.

Pulling cattle the first time with my 19 i observed the same thing you did

 

I ran into this very issue a couple weeks ago and it almost killed me. I was driving my 2018 F350 SRW with slide-in camper (11,500 GVW) down a very steep grade on the Million Dollar Highway outside Ouray, CO when it was my turn to pass a semi truck that was doing 20MPH. The 6.7 has lots of power so I wasn't concerned about passing this truck especially down hill. I was at 3000 RPM in 2nd with exhaust brake engaged and manually moved it up to 4th so I could use higher gears for speed during to pass. I hammered it and hit redline in 2nd when I reached the back of the truck trailer and no upshift! Full throttle, engine was screaming but I could not go any faster. With no upshift to 3rd or 4th I did not have the speed to get around the truck. There are no shoulders on this highway. I had to hit the brakes and pull back in behind the truck before the next turn. Cars behind me thought I was crazy. Luckily no one was hurt.

I have noticed at other times on this same highway that it would rev pretty high when going down hill with exhaust brake engaged and not go into the next higher gear when I add throttle. Very annoying. There are times when you need to go from exhaust brake on the full throttle with upshifts going downhill.

I did not try driving down the grades without the exhaust brake engaged to see what happens. What's the point of an exhaust brake if you can't use it.

Surely there this is a design flaw that needs to be corrected.

Paul