Jump to content

Allison manual mode

Recommended Posts

Hello again.

I have a 06 2500HD with the 8.1L and six speed Ally. LOVE THIS TRUCK!!


Do all the Allison trucks have the manual mode (plus/minus switch on the gear column)?


I havent towed with it yet. I have used the Tow/Haul switch several time, works very well going down hills, but what about the manual mode?


When I put the gear lever down into the "M" position, the indicator on the dash shows the different gear selections, with the "1" being in brackets.


I havent played with it too much, several times i have shifted down into "M" without noticing it and wondered why the truck hadnt shifted into second yet, looking down, i see why.


It seems to be, by using the manual mode, is almost like a second Tow/Haul mode.


Just passed 1000 miles today, so, i still have ALOT of learning to do with this truck.


Anyhoo, just wanted to see what you all had to say.




Link to comment
Share on other sites

First, I recommend reading the manual. You can learn a lot from that.

The six-speed Allison gets the "manual" mode. Really, it is the same as the old "use the column shifter" method, but there is not enought room to put 9 detents on the shifter, so they use 5 detents and an upshift/downshift button.

If you are driving on the highway and put it into manual mode you will get a 5 or 6 in brackets-it is telling you what gear you have it in.

Tow/Haul raises shift points and line pressures, as well as locking the torque converter in all but first gear. It is meant to help the transmission last longer when the truck is loaded. Just downshifting (manual mode) doesn't do anything but allow you to stay in a lower gear.


Good luck and enjoy!

Link to comment
Share on other sites


This topic is now archived and is closed to further replies.

  • Create New...

Important Information

By using this site, you agree to our Terms of Use.