2014 gmc z71 slt drive across the USA and two questions for anyone tha

Bluejeeprubi · September 27, 2013

I am done driving for the night and stopped for the night in Spokane Wa. Tomorrow I will finish my trip from Jacksonville Fl to Seattle Wa. My truck had 1400 miles on it before my trip and had to have the intelllink replaced before I left. The truck has performed perfect so far. From temps near 100 in Florida to a snow storm near "drive to the sun" MT it has been a pleasure to drive. The truck handled great. However, the rear got away from me when I was trying to keep up with a BMW in some twisting roads, but that was my fault. Can anyone explain the auto on the 4x4 dial (did not explain it in OM) and how do you know hill decent is engaged? Thanks

Tim99GT · September 27, 2013

Auto mode will drive in two wheel drive and will engage for wheel drive when the tires are slipping. I would only use it in inclement weather/ terrain. Aka snow storm or something similar.

Hill desent is on when the button is pressed and the light on the button turns on. (Yellow I believe).

I have the bench seat and mine is below the radio next to the cargo light button.

Edit: just looked and there is no light on the hill desent button, but it will notify you on the DIC if it's engaged

stiggy1 · September 28, 2013

From owners manual:

This vehicle has an HSA feature, which may be useful when the vehicle is stopped on a grade. This

feature is designed to prevent the vehicle from rolling, either forward or rearward, during vehicle drive off. After you completely stop and hold

the vehicle in a complete standstill on a grade, HSA will automatically activate. During the transition period

between when you release the brake pedal and start to accelerate to drive off on a grade, HSA holds the braking pressure for a maximum

of two seconds to ensure that there is no rolling. The brakes will automatically release when the accelerator pedal is applied within

the two-second window. If the vehicle is equipped with the Integrated Trailer Brake Control

(ITBC) system, HSA may also apply the trailer brakes. It will not activate if the vehicle is in a drive gear and facing downhill or if the vehicle is

facing up

BringTheRain403 · September 28, 2013

Hill decent not hill hold...

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Bluejeeprubi · September 28, 2013

Was not asking about hsa was asking about the hill decent button next to the parking assist button. Mine will not light up when pressed or give any indication that it is on (ie light turns on when traction control is off). I had to replace my intelllink prior to leaving and was curious if it might have messed something up.

BringTheRain403 · September 28, 2013

I'll look at my button today. I know for a fact when I was messing around with it last week it was giving me messages in the DIC...

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Zane · September 28, 2013

Was not asking about hsa was asking about the hill decent button next to the parking assist button. Mine will not light up when pressed or give any indication that it is on (ie light turns on when traction control is off). I had to replace my intelllink prior to leaving and was curious if it might have messed something up.

I'm pretty sure it only works under 10 or 15MPH. It's for low speed only, ie trails and off-roading.

TheElementalCashew · September 28, 2013

Was not asking about hsa was asking about the hill decent button next to the parking assist button. Mine will not light up when pressed or give any indication that it is on (ie light turns on when traction control is off). I had to replace my intelllink prior to leaving and was curious if it might have messed something up.

My button doesn't light up either, but when I was driving through Tenessee and some mountains, I was lightly on the brakes while descending in order to maintain my speed. The hill descent engaged automatically, notified me on the DIC, and started automatically engine braking. You'll know when it is engaged. That is the only time I've ever had it engage.

Zane · September 28, 2013

My button doesn't light up either, but when I was driving through Tenessee and some mountains, I was lightly on the brakes while descending in order to maintain my speed. The hill descent engaged automatically, notified me on the DIC, and started automatically engine braking. You'll know when it is engaged. That is the only time I've ever had it engage.

I think what you saw was the "automatic grade braking".. not hill decent. It uses the transmission/engine as a brake to maintain speed on a steep decline.

TheElementalCashew · September 28, 2013

I think what you saw was the "automatic grade braking".. not hill decent. It uses the transmission/engine as a brake to maintain speed on a steep decline.

Indeed, I thought that is what he was talking about. I thought that they were the same thing?

TheElementalCashew · September 28, 2013

Answered my own question, apparently not.

The Z71 package also includes Hill Descent Control. Engaged by the
driver using a button on the instrument panel, it uses the anti-lock
braking system to enable a smooth and controlled descent in rough
terrain.

The transmissions feature Auto Grade Braking, which downshifts on downgrades to help reduce brake wear.

DRS 95 Silverado · September 28, 2013

Hill desent comes with the Z71 package and the all terrain. You have to enage it before you go down a steep hill, embankment etc. The button is on the bottom of center stack and you with see a light in the cluster.

TheElementalCashew · November 18, 2013

For those who care, I did figure out how the hill descent control works. If you push the button for it in the center console, and at the same time push the cruise control button on the steering wheel, the hill descent control will engage.