Engine braking on 2017 F150 5.0L

Every newer truck with tow haul, including a 5.0 F150 6 speed will take the engine up to or near redline when it downshifts in a grade braking scenario.
The question is what is your perception or definition of really high and downshifts hard?
Truck is 6 years old, so is this a new condition or new to you truck, or something you just noticed?
And fwiw, engine stress at any rpm in this scenario are far less than full throttle under load at the same rpm’s, which the engine is obviously designed for, so no worry about the engine.

Trans is also designed for high rpm downshifts in the same conditions.

Whatever you are comfortable with as long as your TT brakes work well.
The tow/haul downshifting works great when hauling a heavy load in the bed.

I'm pretty sure the engineers that designed Tow/Haul mode know what they are doing. Frankly, I think it works great.

Compare the RPM you see on the tach to the RPM max HP in the book. I would think engine would be designed to spin fast enough to get to rated horsepower without damage.

Let it rev.

On a steep downhill, with 10K pushing me, I prefer to not use t/h, and manually select gear I want to use. This works best for me, on long downhills, that also include lots of turns.

Jerry

Define "really high."

In my experience people start having kittens when their engine RPMs exceed 2000 for some reason.

If you are going down a steep incline really high revving is maybe normal. If your running on flat ground and brake there maybe some revving , but it shouldn't be really high. Are you braking too hard? The harder you brake the more stopping force and revving you create.

MFL wrote:
On a steep downhill, with 10K pushing me, I prefer to not use t/h, and manually select gear I want to use. This works best for me, on long downhills, that also include lots of turns.

Jerry

Not sure I’ve seen a manual mode (+/- button) on any newer truck that will prevent further downshifting if the truck calls for it. Either slowing down below min speed for the top gear selected or in a grade braking scenario.
From the old 6 speed Fords that the OP has to new GM 10speeds.
They’re great at limiting up shifts to whatever top gear you want to maintain.

I don't like the T/H mode going downhill either.. There are times I just need to tap the brakes.. Not prompt a full downshift to a lower gear.

I can manually select what gear I want to use, so I prefer to do that. I know how to NOT ride the brakes and such, so that's not an issue.

I do like it on the flats, so that if I do happen to have to hit the brakes hard for whatever reason, the downshifting helps slow it down.

I neither leave it on all the time, or leave it off.. I turn it on/off as the terrain dictates and the driving conditions at that time.

Works for me. :)

Mitch