+/- Shifting

[dsprik]

I have the +/- manual shift on my new 3500HD D/A . I tried it a little, but couldn't get comfortable with it. I did our semi-annual 1,400 mile trip between Mich and FL in Oct and I left it in auto all the way. Ran incredibly well the entire way, including the TN mountains. What do you use the manual for? I can't see a purpose when this truck doesn't even work hauling the Montana up and down the mountains?

[BB_TX]

I have that same manual +/- shift function on my F350. But like you I have not found a use for it.
I was hunting last weekend with lots of rain and mud. Difficult getting to/from cabin thru the pasture but even in that I could see no use for the manual function. With all tires spinning in the mud transmission was not up/down shifting. Just maintaining a constant pull.
Certainly no need for it on the highway.

[scott-pati]

I use it to keep my rpms around 2k in mountain areas or to keep it from up shifting in stop and go traffic.

[jsmitfl]

I love mine. You can control everything about the trannie, up, down,\hold in gear. Plus along with the extra brake they put on there now, It's all great. I know coming over Teton pass will give you the white knuckles if you don't have it. If you only knew how many trucks have actually used the ramps. I just think it will help wear and tear on brakes.

Dave, When you go back to Michigan, leave your tranny in Drive going up the Mtn. When you get to the top shift in to Manual. It will hold the same gear you are running in at that time. If you need to shift up do so. if you are starting to to go down hill shift down one gear, and another if need be, as you get to the bottom I shift up manually till I don't need the manual anymore. Then into Drive. I think the more you use it you will like it. I just don't like going so fast down hill. Been a flatlander to long.

[Irlpguy]

Like scott-pati I have the Ram 3500 and in tow/haul with the exhaust brake on coming down a hill the transmission will want to shift down more than I want it to at times, by using the manual shift I can keep it in 4th or whatever and up or down shift as needed.

I have not found I need it much to prevent up shifts but sure like it towing the Monty in the mountains.

[dsprik]

Thanks. So It is more useful going down a hill/grade than going up?

[Montana Sky]

I use it for holding specific gears going down the long grades. I also use it for when hitting off ramps and use it to down shift to slow the truck rather than applying the brakes all the time.

[dsprik]

It seems as though the tow haul mode does some of this? Does this +/- function then cancel the tow haul mode?

[dsprik]

The big test will be going DOWN Rarity Mountain in TN when I head back to Mich in April. That is the longest, steepest grade going north on I-75.

[TLightning]

Once in a while, I'll use it down hill. Otherwise I figure the Allison is smarter than I am, so I let it do the thinking.

[BB_TX]

I guess I will have to experiment with it next summer on our annual Colorado trip. This last summer I just left it in D and tow/haul mode the whole trip. It did great going up and down the mountain passes. Saw no need for any manual manipulation.

[DQDick]

I have used it twice on very steep long grades. Most of the time the tow/haul with the exhaust brake take care of it all on their own.

[WeBeFulltime]

There is a good reason that many of the trucking operations both large and small are going to the auto-shift transmissions. The truck's computer is much better than the driver for selecting the proper gear for best MPG. I found that the manual mode was best used in ice or snow so the driver could have better control of the rig in those conditions.

[Mudchief]

Dave most of the time the tow/haul works great. However on some grades going down where it varies a little, the tow/haul tends to up shift causing you to have to hit the brakes to make it down shift again. That is when the manual shift works better.

[steelpony5555]

For those long steep down hills that the exhaust brake can't hold it back on...

[bigred715]

In my 2007 3500 I have yet to use the manual shift, but may try it when heading to Arizona next week. We have 2 steep mountain passes on the way down and I hate it when tow haul winds the engine up too high. Locking in a lower gear at the peak of the pass will hoefully keep it slowed down. I sometimes jab the trailer brakes to slow everything down when the rpm's get too high.

[jhudson]

quote:Originally posted by Mudchief

Dave most of the time the tow/haul works great. However on some grades going down where it varies a little, the tow/haul tends to up shift causing you to have to hit the brakes to make it down shift again. That is when the manual shift works better.

X2, I found when on some Colorado mountain passes when going down, the manual will keep you from having to hit the brakes as the computer may shift the transmission to a higher gear. Most of the time however, I just keep it in tow/haul.