TorqueShift Behavior
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TorqueShift Behavior
I am just getting to know my new (to me) 2005 F250, V10, TorqueShift with the 4.10's.
I really like how the transmission is performing and find the Tow/Haul mode really impressive descending hills.
I do have one question about the TorqueShift. I go down a steep gravel road to my house at under 5 mph. When the road is icy I am very slow and careful. At the top of the hill, in Tow/Haul mode, I start to break and the tranny drops into low gear. Where as all the shifting is quite smooth on this transmission, this drop into low gear is quite pronounced. Is this something I should be concerned about? Or is it the nature of the beast?
I really like how the transmission is performing and find the Tow/Haul mode really impressive descending hills.
I do have one question about the TorqueShift. I go down a steep gravel road to my house at under 5 mph. When the road is icy I am very slow and careful. At the top of the hill, in Tow/Haul mode, I start to break and the tranny drops into low gear. Where as all the shifting is quite smooth on this transmission, this drop into low gear is quite pronounced. Is this something I should be concerned about? Or is it the nature of the beast?
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Today, at work, I grabbed one of the V10's that was loaded with sand and went out to a hill to try to duplicate what my truck does.
Sure enough, in Tow/Haul mode, right after I applied the brakes, it kind of thumped down into low.
Sure enough, in Tow/Haul mode, right after I applied the brakes, it kind of thumped down into low.
Frmr Ford Trans Engr
Joined: Aug 1999
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From: SE Florida
The problem is the 3-2 shift in tow/haul. That shift consists of two clutches releasing while two other clutches are applying. All four clutches have to be timed so that each one finishes what it is doing within 30 milliseconds (0.030 seconds) of each of the other clutches or the shift is going to be harsh.
It is very, very difficult to make that happen. If the timing is off by a few milliseconds you get a thump. The larger the difference from the first clutch to complete to the last clutch the more pronounced the shift will be.
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Joined: Jul 2010
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I don't know if you were pulling a trailer or not but it is designed to "tow or haul" it can get you in trouble on icy roads, kind of like hitting the jake brake in a semi with no load on ice it's a no no unless you know the truck real well.
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