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Class C downshifting ?

jstrong499
Explorer
Explorer
When auto towing with our Ford 450 class C and climbing a slight to moderate hills, the coach downshits and revs really hard and it drives me nuts. Makes me wish the Coach was a manual shift, then all this will go away. Any thoughts or technics beside adding throttle prior to climbing the hill.
Like to hear folks dealing with the same thing
Thanks,
Jamie
21 REPLIES 21

Sam_Spade
Explorer
Explorer
jstrong499 wrote:

Like to hear folks dealing with the same thing
Thanks,
Jamie


You can minimize that downshifting by:

Being sure you are NOT in the tow/haul mode.....
And NOT using the cruise control.

You can minimize it a bit by "charging the hills" and by letting your speed drop slightly going up.

But you can't eliminate it completely. That's the way it is designed to work.

While it sounds like it's going to fly apart, it probably doesn't rev about 4K and will be perfectly fine.

My 450 did that when pulling a trailer, even going over overpasses on the Interstate sometimes. My Workhorse A does it some too.
'07 Damon Outlaw 3611
CanAm Spyder in the "trunk"

ppine
Explorer II
Explorer II
Take a look at the power band for your engine. Do some reading about it and then get a tuner and control your shift points. Most engines are much happier in a lower gear and a slower speed when pulling hills.

TheLuvShack
Explorer
Explorer
Search 5 Star Tune on this forum and irv2.com/forums. I have it and it made a dramatic difference on my 6.8L V10 with five speed transmission. They also reprogram diesels.
"If the women don't find you handsome, they better find you handy". Red Green

Daryl

micpib1
Explorer
Explorer
If anyone finds a way to manually control the Ford 6 Speed Auto Transmission that came in my F53 Chassis, I would gladly purchase it. Any aftermarket engineers out there looking for a challenge? My Diesel Pusher with the 6 Speed Alison had a control pad that would allow me to put it in Drive and let the onboard computer do it's thing or I could manually shift or hold gears. This option gave me the best of both worlds. My Ram Pickup allows the same thing. Please... anyone??? JH

DrewE
Explorer II
Explorer II
If you aren't doings so already, try engaging tow/haul. It will still downshift, but the shift points are a little more appropriate for a heavy vehicle and it should hold in gear a little more reliably, both going up and down.

As others have said, though, the V10 needs to rev quite a bit, particularly for a truck engine, to generate power. If it didn't downshift and rev up it would be quite a dog on the hills. It's just the nature of the beast. Although it may sound like it's going to shred itself to pieces, the engine is quite capable of running at the higher rpm's for reasonably long times without trouble.

Some people here have put in four star tunes and reported good results; among other things, they can tinker with the shift points some.

(Another way to improve this would be to get a newer motorhome with the six speed transmission, which has somewhat closer and more evenly spaced gear ranges. I think there are also some aftermarket overdrive/gear splitter units available that should help a lot...for a price.)

time2roll
Nomad
Nomad

azdryheat
Explorer
Explorer
That V-10 is revving because that's where the horsepower is. I've climbed grades at 4,000 rpm and that V-10 is happy there. Turn up the radio and let it rev.
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