Turning off Active Grade Braking

fjtort2 · May 11, 2016

I read over in the half ton forum about turning off active grade braking with out a trailer.

Been messing with it over a week now on and off. Seems to shift better overall and a little better fuel economy. On a 15 6.0 2500. Has anyone else tried this?

newdude · May 11, 2016

Tried it. Made no difference to me at all.

SouthpawHD · May 11, 2016

I thought the active grade braking was only if the trailer was attached and plugged in?

I've read some other comments on the 1500 forum, I think there is a lot of placebo affect going on.

Skeld · May 11, 2016

How do you turn it off?

crankman · May 11, 2016

Hmmm mine shifts smooth havent tried that.

Nathan79 · May 12, 2016

How do you turn it off?

Hold down tow haul button for a few seconds. When you let up it will say on the screen that it was disabled.

Edited May 12, 2016 by Nathan79

diyer2 · May 12, 2016

Hold down tow haul button for a few seconds. When you let up it will say on the screen that it was disabled.

Does this work on a 2012?

Skeld · May 12, 2016

Holding down the button does work, but the manual would lead me to believe it only effects the operation of the vehicle to have it turned off when the vehicle is in Tow/Haul Mode?

Nathan79 · May 12, 2016

There is Normal Mode Grade Braking, Tow Haul Mode Grade Braking and Cruise control grade braking. Normal mode grade braking is active all the time. However, according to the manual a message is supposed to pop up the first time the system engages within each key cycle.

Skeld · May 12, 2016

I only have 1,200 miles on my truck but I have seen this message twice maybe while driving normally, not Tow/Haul. I'll pay more attention next time to the wording of the message.

Chebbyfan · May 13, 2016

So is this like the traction control, you have to turn it off EVERY time you get in the truck to make it work? There is no way to set it and forget it?

newdude · May 13, 2016

Lets all clarify shall we?

Some further clarification and a video on operation can be found here: http://sandyblogs.com/techlink/?p=1973

Normal Powertrain Grade Braking:

- For grade braking to activate it requires the driver to apply steady brake pedal pressure to maintain desired speed while driving on a downhill grade. The vehicle's modules monitor the amount of brake pedal apply, vehicle deceleration rates, and other factors to determine if normal mode powertrain grade braking is necessary. When the feature activates for the first time that ignition cycle, the DIC will display "Grade Braking On" or "Grade Braking Active" and you will notice the transmission down shifts and engine RPM increases. At this point, if the brake pedal is released the transmission will hold the current gear. If additional engine/transmission braking is needed to help maintain desired speed, reapply steady brake pedal pressure and additional down shifts may occur.

-Normal mode powertrain grade braking will have a less aggressive transmission down shift schedule than Tow/Haul mode powertrain grade braking.

-Grade-braking can be exited by depressing the accelerator pedal.

This is on all the time. You have to have a steady brake pedal application down a grade for it to kick in. I have activated it on purpose before to see if it works, and boy, it does.

GRADE BRAKING OFF: This message displays when the grade braking has been disabled with the tow/haul mode button on the end of the shift lever.

GRADE BRAKING ON: This message displays when the grade braking has been enabled with the tow/haul mode button on the end of the shift lever.

GRADE BRAKING ACTIVE: This message displays when the grade braking has been activated while driving on downhill grades. This message will only appear the first time the feature is activated in an ignition cycle. This message will not display if Cruise Control Grade Braking goes active.

Tow/Haul Mode:

Tow/haul mode is a function within the vehicle's software/calibration that optimizes transmission gear selection for operation during towing or with heavy loads. This optimization includes improving acceleration performance during launches, reducing shift busyness, assisting brake performance and speed control during engine braking situations, and improving vehicle speed control while requiring less throttle pedal activity.

In general, tow/haul mode maintains lower gears longer and increases shift pressures. It is designed to be most effective when the vehicle and trailer combined weight is at least 75% of the vehicle's Gross Combined Weight Rating (GCWR). Operation of tow/haul in a lightly loaded or non-loaded vehicle will not cause damage. However, there is no benefit to the selection of tow/haul when the vehicle is unloaded, and use of tow/haul mode during unloaded driving conditions will decrease fuel economy and may generate shift feel concerns.

So, all trucks 2007-2016 have Tow/Haul Powertrain Grade Braking. 2013 and newer trucks have Normal Powertrain Grade Braking, which is a less severe (if you will) setting than the Tow/Haul Powertrain Grade Braking. 2012 and prior trucks do not have the Normal Powertrain Grade Braking, but do have the Tow/Haul Powertrain Grade Braking.

Cruise Control Grade Braking:

Vehicles with a six speed automatic transmission and a gasoline engine have Cruise Grade Braking to help maintain driver selected speed.

Cruise Grade Braking is enabled when the vehicle is started and Cruise Control is active. It is not enabled in Range Selection Mode. It assists in maintaining driver selected speed when driving on downhill grades by using the engine and transmission to slow the vehicle.

To disable and enable Cruise Grade Braking for the current ignition key cycle, press and hold the Tow/Haul button for three seconds. A DIC message displays. See Transmission Messages.

Vehicles with a diesel engine have Cruise Grade Braking enabled when Tow/Haul Mode is on, the exhaust brake is on, or both are on.

I thought the active grade braking was only if the trailer was attached and plugged in?

I've read some other comments on the 1500 forum, I think there is a lot of placebo affect going on.

No. Powertrain Grade Braking is on at every key cycle. A message only pops up the first time it is actually activated. It is disabled in manual (M) mode. Holding the Tow/Haul button for 3 seconds disables it as well.

Hold down tow haul button for a few seconds. When you let up it will say on the screen that it was disabled.

Does this work on a 2012?

2012 trucks have Tow/Haul grade braking, and Cruise Control grade braking. 2013 and newer trucks have the Powertrain Grade Braking feature.

So is this like the traction control, you have to turn it off EVERY time you get in the truck to make it work? There is no way to set it and forget it?

Yes but there is no real reason to turn it off as it makes no difference really. It only is active when it needs to be (say riding your brakes for a bit down a hill).

Edited May 13, 2016 by 15HDriver

rocknfire · May 13, 2016

It makes a huge difference on my truck. 15 half ton with the 5.3

Jparker2012 · May 16, 2016

On my old halfton with the max tow package it shifted like absolute Garbage in tow haul mode and the 8 speed. It had the 6.2L and was a really nice truck but the ruff shifting ultimately led me to trade it for a Duramax, and I'm glad I did!

Sent from my SM-G920V using Tapatalk

sk · May 16, 2016

Yes but there is no real reason to turn it off as it makes no difference really. It only is active when it needs to be (say riding your brakes for a bit down a hill).

That is the way it is SUPPOSED to work but many folks with 1500's have noticed a huge improvement in transmission "smoothness" if you disable it before you begin driving. The theory is that the software is not programmed correctly and that the grade braking is not working like the manual says it should (instead of only being active if you ride the brakes it is actually trying to kick in when you coast and makes the transmission do more hunting for the correct gear). There are already some dealers that have tried this and proven that it helps. They are passing the info back to GM Engineers to see what they say.

Edited May 16, 2016 by sk