Jump to content

Grade Braking

Danimal13

Recommended Posts

Danimal13 Enthusiast

Danimal13

Posted
Posted

Today exiting off the interstate on a flat road, just coasting, the info center displayed a message saying "grade braking active" I was probably around 60 mph on flat road...any ideas why that would show up? 2015 Denali 6.2 with 3800 miles and first time I ever saw this.

 

 

Sent from my iPhone using Tapatalk

jamesonjc Enthusiast

jamesonjc

Posted
Posted

were you in tow mode?

 

This happens often to me when driving in tow mode but mostly on hilly roads on the north shore of the island.

 

JC

newdude Senior Enthusiast

newdude

Posted
Posted

Hmm... interesting but normal. Powertrain Grade Braking is on or armed if you will with each ignition cycle. Strange that it said it on a flat ground. Were you applying any sort of brake pedal pressure be it light or moderate? Typically when it sees light, constant pedal pressure, it will activate the grade braking.

smrr1 Senior Enthusiast

smrr1

Posted
Posted

Mine will come on with even the slightest down hill angle. What most people would consider flat ground. Only if i am coasting or lightly on the brakes.

redwngr Senior Enthusiast

redwngr

Posted
Posted

There is also a 'cruise grade braking' function that can activate to keep the speed from climbing when in cruise on a downgrade.

awd_rs Enthusiast

awd_rs

Posted
Posted

Grade braking is activated when the brakes reach a specific temp . Really does not matter if your going down hill or not . If you ride the brakes just enough it will activate . It is not tow/haul mode specific either .

avgas Enthusiast

avgas

Posted
Posted

Grade braking is activated when the brakes reach a specific temp . Really does not matter if your going down hill or not . If you ride the brakes just enough it will activate . It is not tow/haul mode specific either .

I don't think it has anything to do with brake temperature. Any literature I have read from GM says it can help keep the brakes 100 deg cooler but that is the only reference to brake temp. It monitors grade and brake application to activate.

awd_rs Enthusiast

awd_rs

Posted
Posted

"To disable or enable all grade braking within the current ignition key cycle, press and hold the Tow/Haul button for three seconds. This feature requires the driver to apply steady brake pedal pressure to maintain desired speed while driving on a downhill grade. The vehicle's modules calculate brake temperature and enable Normal mode Powertrain Grade Braking if necessary. The transmission downshifts 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 downshifts may occur"

 

http://www.acdelcotechconnect.com/pdf/TechConnect_SepOct_2013.pdf

avgas Enthusiast

avgas

Posted
Posted

"To disable or enable all grade braking within the current ignition key cycle, press and hold the Tow/Haul button for three seconds. This feature requires the driver to apply steady brake pedal pressure to maintain desired speed while driving on a downhill grade. The vehicle's modules calculate brake temperature and enable Normal mode Powertrain Grade Braking if necessary. The transmission downshifts 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 downshifts may occur"

 

http://www.acdelcotechconnect.com/pdf/TechConnect_SepOct_2013.pdf

So it's a calculated temperature then not an actual temperature of the brakes. The calculation is way off, -30 deg C and the grade braking comes on when there is no way in hell the brakes are the same temp when it's +25 deg C. Same road same speed everyday and grade braking comes on like clock work. I think GM is trying to make it sound a lot more technical than it really is. If it worked off of brake temperature and not "grade" it should be coming on during heavy braking in all conditions. I can't say this feature really does a whole lot, Just something we are paying for like the engine braking feature that is useless.

Archived

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

Go to topic listing

  • Latest Articles

  • Posts

    • Brendan C
      2026 6.6 L5P oil cooler leaking oil at 4,000 miles

      By Brendan C · Posted

      New to diesel trucks. I happened to find my oil cooler leaking oil externally with only 4,000 miles on the truck. I didn’t realize this was an issue until I started researching it. Dealer is going to replace it under warranty but I’m wondering if there’s anything GM is working on to fix this issue. I’ve heard the oil filter used is the same as they use on their V6 motors and that’s what is causing the problems. Should I switch to a bigger filter or keep using the OEM recommended? 
    • Vu1can
      Seems to be Missing a lot of Updates

      By Vu1can · Posted

      So, GMCustomerService:  Judging by the Update History pictured above, is this truck missing any updates that it actually needs. If it's just for the infotainment system, the radio is working fine and no trouble with SeriusXM. and Android Auto is working fine wirelessly with my phone. Some months ago, an update notice was sent to my truck. I approved the update and it finished saying that the update was successful, but it seems that whatever that update was, it didn't actually get installed - at least not if I'm to go by the Update History shown above.   So, again, are there any updates that this truck really should have? I've checked with my dealer but they're reluctant or commit to anything and if I want them to check, they require a $200.00 fee just to check it out and then I'd have to pay for the actual update(s).    Ignorance is bliss, and if none of the updates goes to fixing any mechanical discrepancies, I'll just leave things as is.  
    • CNH-320
      Electrical Problem - solved

      By CNH-320 · Posted

      Hey everyone, I recently had an issue with my 07 2500HD GMT900. My DRL’s stay on at all times. Right front turn and right mirror turn signal indicator stay on solid at all times. By “at all times” I mean the only way to make them go off is disconnecting the battery. I tore the headlight assemblies out, tried disconnecting the harnesses to eliminate bad wiring at the harness, I unplugged the headlight switch, no change and the mirror turn signal still stayed on. My first thoughts were : Bad bulb and/or socket somewhere, under hood fuse panel bad, bcm bad, tail light or trailer wiring problem, or some random short to power in the harness.  Possibly a bad ground but unlikely. I had a big clue in the fuse panel, it had a burnt smell. I started pulling every fuse that had to do with DRL or right turn/park lamp. Nothing made the right directional turn off but pulling the DRL2 fuse made the DRL’s go out.  After studying wiring diagrams, I found that both problems had that fuse panel in common, the bcm also controls both problems but knowing the fuse panel had a burnt smell I removed and disassembled the fuse panel and found a little corrosion on the printed circuit board.  I ordered a new fuse panel from Amazon for like $260. When it arrived I installed it, and put everything back together, the problem was fixed. I figured the fuse panel needed to be replaced anyway so that was a logical place to start. Hopefully this story helps someone in the future. Regretfully I didn’t scan for codes before I did everything.
    • 2022LtTbZ71
      Service 4wd, ESC light, traction control light on, Service charging system (vehicle may stall)

      By 2022LtTbZ71 · Posted

      That stinks. I’m sitting on the side of the road right now with the same issue. Never had an issue before taking it in for the ground strap recall. Now I’m outside of warranty and they’ll probably want $200 just to diagnose what they already “fixed”. 
    • jagabom (Esquire)
      Passenger seat

      By jagabom (Esquire) · Posted

      I wonder kind of nuts and bolts they will come up with next? Jim

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...