I have a 08 3500 dually, 4wd, 4dr. My problem with the truck is the way it shifts, the upshifts de-fuel to the point of its like riding a rocking horse and the other real pain in the a$$ is when you let off the throttle and coast for a bit from say 35mph when you pick the throttle back up it like lags and then all the sudden catches up. It almost feels like it has a bunch of drive line slop but of course it does not!
Now the interesting thing it does not exhibit any of these traits in tow haul mode, driving empty. I have a Quadzilla programmer and it does all of this with stock/ dpf delete prog or any of the hot programs, actually the up power programs suck so Bad I wont run them hat the shifting big time.

What I dont like about the tow haul mode is the higher rpm shift points for daily driving and the down shift points, but love the shift feel/firmness and the fact it does not seem to do the couple un-couple of the transmission .

So with this all being said:

What would be a good programming system to get and have the ability to tune a program in like the tow haul but with my tweaks?
I really would get rid of the truck but I do like it it just sucks the way it shifts, a new one is still exactly like what I have so it would just be new and hopefully it would shift correct. But that is not what I want to do I just want it to shift right and you all know the dealers wont fix S&*t unless it's thrown a code....................idiots!

The only thing out there for making changes to the TCM is EFILive using the hardware Flashscan V2 device. To play with you can download the latest V7.5 (NOT THE V8 SOFTWARE) and it will run in demo mode. Download one of the TCM stock tunes out of the EFILive library here and see if you can handle making the changes you think you may want. Editing the TCM can be tricky and best to make minor changes at a time. But you can remove the defueling and so forth with EFILive. If your Allison is not a built one to handle high HP tunes and you start to remove the saftey like defueling then it is not gonna last long. Be prepared to have it rebuilt and do something like a suncoast, ppe, or ats kit. If you think EFILive is for you then I suggest buying from one of the many good tuners here. This way you can get support, one or two free tunes to get you going is what most do. Only dealt with Nick from DuramaxTuner. I have a TCM tune from him that works real well. I just would not use it on a stock Allison.

Brian

Sounds like you need to change your fuel filter to me.

The more I re-read that post and mention of the same issue in stock tuning then I agree change the fuel filter. If you are in cold climate area then possible fuel gelling. Change fuel filter and add some anti-gelling additive.

Brian

x's 2 on the fuel filter...same problem here. fixed with new filter. of course i go through filters like i change socks...will be purchasing fuel pump here shortly