Downshifting While Towing

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Jun 1, 2006 | 01:33 PM

snsgraham

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Downshifting While Towing

A rather quick question here.

When towing my 11,00 pound 28’ Desert Fox at highway speeds, should I let the truck decide which gear to choose or should I manually shift down for hills? I am thinking of the best sort of downshift for transmission life here, sometimes it seems to shift sort of hard on its own, mostly when dropping into second gear.

See my sig for truck info.
Thanks guys,

Scott

PS I will eventually put 4:30's in this thing, just not this year.

Jun 1, 2006 | 03:14 PM

biz4two

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Joined: Sep 2003

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From: Albuquerque

IMHO...it is only necessary to manual shift your 4R100 auto tranny while towing is going from over-drive to 3rd. And that should only happen when the trans cannot make up its mind. If it is shifting in and out on a slight grade, then it is best to push the button off...and let the tranny stay in 3rd. Helps reduce heat and wear on the tranny.

As for climbing steep grades like mountain passes, then I usually let 2nd come all by itself (pedal to the floor).

Hope this helps...

biz

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2003 F250 SD SC 142" XLT FX4 V10 Auto 4x4 3.73s

Jun 1, 2006 | 03:54 PM

snsgraham

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biz,
That is just about exactly what I am doing now. Sometimes the automatic downshift to second is pretty hard though, just wondering about the transmission...

Scott

Jun 1, 2006 | 03:55 PM

FastDEW

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From: Rancho Cucamonga, CA

I guess this is all about opinion and what your comfortable with. I usually shift the truck to 2nd on my own. First off, my truck will not pull my large 5er in OD, so that is out all together... I pull in 3rd on flats. For grades I make the judgement based upon my throttle imput and motor sound. If I feel that the motor is starting to really work and it is heading toward a downshift eventually anyway, I go ahead and drop the gear. If I leave it up to the tranny to decide it will sometimes hold 3rd with the throttle at like 90 - 95% and the engine really lugging hard. The truck pulls much nicer and it is easier on the engine if I just go ahead and drop the trans to 2nd on my own. This also let's me drop the gear while under lighter throttle load which I think is easier on the transmission.

Jun 8, 2006 | 12:43 AM

twayneb

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Joined: Jan 2006

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From: Calgary, Alberta, Canada

A little late on this but I just returned from trailering for 2 weeks. I pull around 10 k with my 2000 F-350 4x4 V10 and find it works best to let the tranny shift on it's own. The only manual shift I do is o/d to 3rd or into 2nd when going down steep hills. As was mentioned earlier if the engine starts to lug, tramp the pedal to the metal. Today this worked well even on an 11% upgrade. The tranny doesn't heat up and the engine runs cool. Question! When was the last time the tranny was seviced? Clean fluid makes a difference and smooths out the shifts.

Jun 8, 2006 | 11:03 AM

FastDEW

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From: Rancho Cucamonga, CA

I service my tranny regularly. I have the fluid pump through with an exchange pump.

As for the throttle to the floor example. My truck has always (since new) had trouble with this. I mean that often if you floor it under load after it has pulled a grade for some time, it will not downshift. You have to pull the gear down manually, the trans won't drop the gear on it's own

Jun 8, 2006 | 02:12 PM

snsgraham

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My transmission is serviced every year, the expensive way..
My local guy here said it was the best protection you can get for it. Everytime he changes it he does say that it looked/smelled just dandy though.

Scott