plasticmaster
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Joined: 10/27/2008
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I have a 2017 F150 with the 5.0 engine. When I tow my TT in tow haul mode, it seems to me that Ford has overdone it with the engine braking. As I apply the brakes, it downshifts really hard and revs really high to the point of making me wonder if it could damage the engine or transmission. On my last trip, I would disengage tow/haul when I knew I was getting ready to hit the brakes. Should I be concerned about this, or just let it do its thing?
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Grit dog
Black Diamond, WA
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Joined: 05/06/2013
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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.
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Boomerweps
Hills of PA
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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.
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wing_zealot
East of the Mississippi
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I'm pretty sure the engineers that designed Tow/Haul mode know what they are doing. Frankly, I think it works great.
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JRscooby
Indepmo
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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.
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Turtle n Peeps
California
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Let it rev.
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MFL
Midwest
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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
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mkirsch
Rochester, NY
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Define "really high."
In my experience people start having kittens when their engine RPMs exceed 2000 for some reason.
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Lantley
Ellicott City, Maryland
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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.
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Grit dog
Black Diamond, WA
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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.
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