JRSPerf.

Thank you for the info., I thought it was very useful and a little disappointed they are gone.

Hello everyone. Can anyone confirm why/if Chevy/GM get rid of the keyless entry buttons on the back exterior doors handles for the Crew Cab 2021? My 2020 3500HD HC DRW had the small lock/unlock button on all (4) exterior door handles, my 2021 3500HD HC DRW only has them on the Front Driver and Passenger exterior door handles, they are optioned exactly the same except for the 21 has the power retractable side steps.

Hello again my friend! Yes that button you are talking about is the "Hill decent control" button, I believe that only works under speeds of 25-30mph. Thank you for your feedback though I really appreciate your time and please keep me updated!

Hello my Friend, what is your build date?

Thank you my friend for the info. The Auto Grade brake feature NOT to be confused with the Exhaust Brake Feature are (2) seperate features. The Auto Grade Brake is ALWAYS active and cannot be turned off like in previous models, I believe the only way for it to not operate is with the vehicle in the Manual Shift Mode. The Exhaust Brake is Turned on/off via a switch and is mainly utilized in tow haul mode. My vehicle being an earlier build date (01/20) was super aggressive when both of these features were active, after it went in for a service visit it received a software update for the DEF(reductant fluid) module SIB and whatever else they had to program which in my opinion completely rendered the Auto Grade brake and the Exhaust brake features basically inoperable. It would now make sense as to why so many people complaining that their Exhaust Brakes don't or do not feel like it is working in their 2020. My vehicle's Auto Grade Brake and Exhaust Brake were AMAZING until that new software. After a certain production date that new software was implemented in the assembly so vehicle's are rolling out to the dealerships that way. My goal was to gather up as many people with early build dates and who's braking features STILL worked the way mine originally did before the update to take back to my service dept. So they can forward the issue to GM. My service dept. has no idea what I am talking about because everything they have to compare has the NEW software version and the inadequate braking features. Really sad that no one will ever get to enjoy the way these systems are suppose to work!!

I really do not understand why more of us are not noticing this change.

Thank you for the feedback, please keep me updated if you get somewhere.

Thank you for the info. I really do appreciate the feedback. It is almost certain that your vehicle was also programmed at that time. I understand what you are saying when you say that yours has operated the same way since day one if that is the case. This is a problem with current level software, not sure of the exact change time frame but that is what we are trying to figure out, also to that point ALL newer vehicle would perform as such(same as yours). Mine was very distinctive in it's operation, light brake application down a grade(hill) in NORMAL drive mode WITHOUT the Exhaust Brake Turned on it would very noticeably down shift and hold a higher RPM until I stepped on the gas pedal to accelerate.

LSPowered65 A friend of mine had an AT4 3500 Build date 08/19 and his did it as well(he no longer owns that vehicle), Maybe bc yours is a 2500!? Not sure but all I know is I have over 20Yrs in the automotive service industry, Dealership Certified Master Technician. I know the way it use to operate and how it does now. Software is the issue. This is why I put this out there, feedback from different members, build dates, 2500 or 3500, all this helps and that is all I am looking for.

That qualifies as a response though! I am not the only one who's vehicle operated this way, check out the post by JHARRIS32 "HIGH RPMs downhill". Has your vehicle been to the service dept.? Any programming, maybe for the "Reductant control module SIB"?

Soooo, not one person on here owns a 2020 duramax and is willing to attach a 10sec. Video clip to help out a fellow member!? Over 100 views on this post and almost 500 on another just like it but not one video!! All I need is a short video to show the service dept. the way it should be operating!! They have nothing there to compare it to. This is something big here and can also help you out in the long run bc I'm telling you if you take your truck in for service and it gets programming you will now be in the same situation I am in now!!! This is to convince GM to take a look into their software to make changes! They are using my truck basically now as test truck to figure this out! GM Engineering is involved but all they have to look to are new trucks with the updated software.

Hello davester. I have a 2020 silverado 3500 hc drw, My build date is 01/20. Long story short my vehicle's auto grade brake function no longer works or at least not operating the way it use to before I had it in for service. Before the service visit I had my vehicle for 6mnths and drove 5kmi. and every time I would go down a decent grade hill if I tapped the brakes the auto grade brake would kick in and hold a higher rpm all the way down until I pressed the gas pedal to accelerate again. After the service visit it no longer does this, at all, it doesn't even drop a gear! It has now lived at the dealership for 47 days bc they can not find anything wrong with it. I believe that when it was in for service and had to be programmed something was inadvertently changed. I just need a video of someone's vehicle who's Auto grade brake in "Normal" drive mode is actually doing what it is suppose to do! This is a weird issue because only the early version/builds operated this way, newer builds with the newer software operate as if its not even there. It drives me nuts because I loved that feature about this truck!! If you could help me out I would be so grateful, thank you my friend.

I am reaching out to our community. If you own a model year 2020 Silverado/Sierra 2500/3500 DURAMAX Please attach a video clip of the instrument cluster while traveling down a grade(hill) and applying the brake briefly to activate the Auto grade brake feature. I am really looking for early production vehicles here but any and all that are MODEL YEAR 2020 will help, the earlier the better. This will not take long and your help will be GREATLY appreciated!! Please note the production date of your vehicle this can be found on the B-pillar placard. Also if the vehicle has been into the dealership for any service/recall/SIB that required your vehicle to programmed(updated software) please note that as well. THANK YOU!!!!!!

Hello JHarris32. At your earliest convenience can you PLEASE attach a short video clip of the instrument cluster(rpm guage) while this situation is occurring. Also please note your vehicle's build date, this can be found on the driver's side b-pillar placard. Thank you so much in advance!!

I am reaching out to our community. If you own a model year 2020 Silverado/Sierra 2500/3500 DURAMAX Please attach a video clip of the instrument cluster while traveling down a grade(hill) and applying the brake briefly to activate the Auto grade brake feature. I am really looking for early production vehicles here but any and all that are MODEL YEAR 2020 will help, the earlier the better. This will not take long and your help will be GREATLY appreciated!! Please note the production date of your vehicle this can be found on the B-pillar placard. Also if the vehicle has been into the dealership for any service/recall/SIB that required your vehicle to programmed(updated software) please note that as well. THANK YOU!!!!!!

What is the build date of your vehicle? Mine is 1/20. Before my vehicle was RECENTLY programmed my "Auto grade brake" & also the "Exhaust brake" was much more aggressive than my 2015 duramax. I actually wasn't even aware that the 2015 had the "Auto grade brake" feature. Yes I was well aware of the "Exhaust brake" in the 15 and it worked well but never once felt the "Auto grade brake" kick in or have the message come up in the dash that this feature was active. It wasn't until 5yrs later when I purchased the 2020 that I was introduced to the "auto grade brake" in "Normal" drive mode feature, not to be confuse with the "Exhaust brake feature". The exhaust brake feature is a manually selected feature(button/switch operated) the "Auto grade brake in "Normal" drive mode is always active on every key cycle in the 2020 and cannot be turned off in the 2020 like it can in the earlier models by holding the tow/haul mode button for 3 sec. The first time I was introduced to the "auto grade brake" In the new 2020 I was coming dwn a decent grade(hill) on a road that I travel every day, I stepped on the brake pedal a little bit and immediately the truck responded by dwn shifting aggressively(feels very similar to the exhaust brake when towing) and held that until I stepped on the gas pedal at the bottom of the hill, never again did I have to step on the brake and if I did it would dwn shift again!! It continued to do this & in my opinion do it very well, on every decent hill including that one that I traveled on and applied the brakes, my absolute favorite "NEW" feature (I thought it was a new feature)on the 2020. . Also the Exhaust brake feature in tow/haul mode is no longer working. I too tow a big 5th wheel toy hauler with my truck same trailer same weight as always and the "Exhaust Brake" use to come in super aggressive(better than the 15) when it was on and I was towing up until that first service visit. Now its as if like you said "the switch is a dummy switch" it has no effect at all!! My problem is, This truck, the 2020 use to do what my 15 did but even better in my opinion because I didn't even know the 15 had the "auto grade brake" in normal drive mode!! Actually in the 2020 my wife sitting in the passenger seat notice it immediately the first time we felt the auto grade brake kick in and asked me if I had the exhaust brake on(I didn't), then she thought something was wrong with the truck because like I said our 2015 that we had bought new until we traded up for the 2020 never did The auto grade brake feature in normal drive mode atleast not to me being able to notice it! This is driving me crazy that they (chevy service) keep telling me that everything is fine when I know it use to do it differently until that visit!! I refuse to eat that crap that this is how it is designed to operate when this exact truck use to do it better!! It would be like them telling me that my drivers window never rolled down, I know it does, you know!? Same thing here, it did it now it doesn't and they tell me that it never did it!! DRIVING ME CRAZY!!!!!

If you are having any issues with your Newly purchased GM vehicle call this lady from GM directly! Her name is Anya and she is a Senior Advisor for General Motors! 1-866-790-5600 ext. 5911370

Yes that is the document for the exhaust brake. Press the button, light comes on, no fault codes, all good as far as chevy service is concerned! They Do not take into account that it operated the exact opposite from day1 to the first service visit! Also no mention about the "auto grade brake feature". That bulletin is dated June 2020, yes I see from & to (all prod.) I'm not making something up here! The vehicle use to do something it no longer does and It stopped doing it after and only after it was programmed. Really not that hard to see the issue here!! That document is a blanket statement also clearly states that the reason why it "feels different" is "Now the turbo charger vanes move slower"! A control module controls an actuator that move the vane assembly and therefore relies on a program to control said function! Why is this so hard for GM to grasp!?!? I'm Not saying that later software developed and installed into later vehicles are not "operating as designed" in fact thats EXACTLY WHAT I'M SAYING HERE!! My vehicle doesn't do something it use to do all that changed is the software!! This is simple logic!!

Gm did have a bulletin on the exhaust brake at one time but it has since disappeared. GM replaced it with what my Service dept. handed me, a GM document stating some customers may have concerns with the exhaust brake operations and how it may feel like it isn't working. It states that if the button is pressed (exhaust brake button) and the message "exhaust brake on" is displayed in the cluster the system is operational, they stand by the fact that this is the way it has been designed to operate for a "better driving experience". No explanation on why the "auto grade brake" is no longer working. They can not however discount the fact that I have had my vehicle for 6 months, drove over 5k miles and my vehicle operated in a very specific way when it came to the auto grade brake and the exhaust braking! I am not concerned with how I believe it should work nor am I concerned with the fact that it doesn't "feel" like it is working. I am not comparing it to how another vehicle feels, I am concern with the fact that MY VEHICLE use to do something a particular way for 6mnths and 5k miles. It no longer does what it use to do and the only thing that happened in between was a service dept. Visit where the vehicle was programmed! There must be a split somewhere in production where the earlier production vehicles software allowed the system to operate the way mine use to, the way It should operate, in a later production vehicle this system seems to be detuned and feels like its not there at all. If you search this issue anywhere there is a very dramatic split where some people are complaining about how aggressive it is and hate the fact that it can not be turned off(auto grade braking) like in the older models (2013-19). Then there is the later production vehicles that feel like this feature isn't even there and is supported by the GM document. This would also explain why my early production vehicle that was programmed with the latest software now operates completely different! Software changes the way vehicles operate this is why they are programmed/updated!! So the fact that someone can say to me that "they would have a tough time believing" that software could inadvertently be the cause of my issue has no clue what they are talking about and should not comment!!

01/20

Hello everyone! I am a new member here and just looking for some clarification if anyone can help. I have a 2020 Silverado 3500HD HC Duramax DRW, 7kmi. My vehicle also suffers from almost every topic in this forum from day 1! From the low thud from engine at idle, steering column/intermediate shaft/ steering box noise, vibration at hw speed, pulling/steering wheel to the right, infotainment cutting out screen blank no audio, transmission bell housing leak, to it sounding like a freight train every time I would come to a stop!! It is so frustrating that a brand new vehicle would have so many issues!! I absolutely love this truck but cannot do the back and forth with the service dept.!! I took it in to address the concerns I had after spending some time driving around. I wrote a detailed list explaining all the concerns and how they could be replicated (night time drop off). I did not receive a phone call from the service department for (4) days, each day my vehicle was in I would try to contact my service advisor but would only get her answering machine, many messages left with no return call! Finally on day (4) she leaves a message that my vehicle was done and may be picked up. I called her back immediately but again only got her machine. I go in to pick up my vehicle and my advisor convientaly left for the day. I spoke to another advisor and went over what was done to address the concerns I had. Most of what I had listed out on my original concern list never even made it to the RO!! They advisor explained that basically there were a few updates performed, programming for the steering control module(vibration issue), reductant module update, radio software update, engine control module programming, road force balance front wheels, retorqued the rear leaf spring brackets & they had to order the front and rear brakes pads. When I asked about the low thud from the engine he said it was normal and would not cause any harm to the long term durability of the engine. When I asked about the rattle/knocking noise from the steering column he said that the steering control module update should also take care of that, I thought that was weird but got in my truck and drove away. Absolutely NONE of the concerns I have are repaired, every single concern is still there!! Also now and this is where I am seeking clarification I noticed that the auto grade braking feature(I absolutely loved) and the Exhaust brake no longer work or at least are not working they way they use too!! Does anyone have this issue after vehicle programming? I am convinced that when the vehicle was programmed to address the other concerns that it either inadvertently programmed out these features or at least changed the drive logic behind how these features operate. I have a long steep hill that I travel down everyday and when coming down this hill (in NORMAL drive mode) originally I would just have to tap my brakes and the trans. would dwn shift as the rpms would jump to 2500/2800 and I would not have to use my brakes again coming dwn this hill as the auto grade braking was doing its job! Now it doesn't even dwn shift, nothing, I have to ride the brakes all the way down the hill. I have a fith wheel toy hauler that I tow with it and yes I followed all the break in periods before towing with the new truck, before the exhaust brake did an amazing job and came in strong to slow the beast down now it doesn't even come on even thought the system is on! I have no fault display messages no fault codes so the dealer tells me everything is working fine. I know for a fact that every thing is definitely not working fine but no fault codes so no problem as far as the service department is concerned! Does anyone have this issue!? Does anyone know if the parameters may have been changed for these systems with new software release as when I research these features I find a ton of people complaining about how aggressive they are especially the auto grade brake and want to turn it off. Sorry this has been a long read if you made it to this point but I am desperate to figure this out.