This would be even better if you could switch tunes on the go. like your at a red light and a corvette pulls up next to you. I wouldnt want to have to turn off my truck to switch tunes.

 

in the gmt900's there is different throttle settings as well for tow/haul mode.

 

Area47, in the gmt900 w/ 6.2 and 6L80, you can use your tow/haul mode for performance settings? Just like nbs 60E's?

 

i have mine setup for a lot firmer and faster shifts. higher pressures and such. so i guess it's a performance mode?

i haven't sat down and dicked with it a lot honestly.

 

Tuning the PCM for firmer shifts/higher pressures I presume would cause more parasitic drag, correct? Increasing line pressure puts more strain on the pump, so....correct?

 

I am not sure why someone would want to change the fuel on the go, unless you swap in a tank of different fuel. I have my tow/haul mode set to hold in first until the throttle is wide opened with the speed at redline. This works real well when the tires break loose on the street, and you have to lift. It won't shift into 2nd, you just get back into it when it stops spinning and go.

When I get my truck back together, I am thinking of adjusting the torque management so that I can get into the throttle harder off the line instead of foot braking it.

 

to have this setup work on a non LS motor truck you just need a momentary push button switch that is normally open.. One press grounds pin 71 on the blue connector.. i forget which one it is for the red/green pcms but that's the way it was for my 02 style harness


after that, HP tuners can change how you turn on towhaul... usually its on "no switch" or "class 2" and you can change it to "one switch" which is where your momentary ground switch comes in

 

So I like the idea of being able to run a bit more aggressive shifting tune with the tow haul, but how would this affect the truck towing? I would love to have a performance setting with my tow haul, but I still also need it to be able to tow within reason.

 

Once it cools off a bit, I'm going to wire in a momentary switch. Sounds like everyone agrees that pin 71 in the blue connector is what needs to be grounded. Then change the performance option in the tune to "one switch". Then I can keep the trans in first gear for 30mph rolls.

 

Pin 71 is what puts the computer into tow haul mode (performance mode in the computer) from my understanding. Basically that is a trick that is used if your vehicle does not have a tow haul button.