Ghosts, Intermittent's, Trust and no answers !!!

Steve.S · November 22, 2020

Sorry in advance for length, but several problems and have not shared everything about them!!!!

Am I crazy? are there ghosts? is any of it real? and it all leads to trust! I know new vehicles have a lot of electronics and they are harder to track down when it only happens occasionally. To me it is the most frustrating to go to the dealer and say this happened, I heard this, the truck did this! and they come back with "Mechanic checked it out thoroughly and everything is OK!" You drive off asking yourself did I really see this? did I do something? did I hit a switch I shouldn't have? The dealer tells you "If it is intermittent, unless we see it here, we cant fix it" And now my Problem, search for help, and seeing if anyone else has seen this?

1. 2020 GMC Sierra Denali 2500HD 6.6 Duramax Diesel. (Which driving off the lot I was so happy about) at about 200 miles I was diving around and noticed that the display in the cluster changed! I thought it was something I did and kind of ignored it. At 300 miles took it to the dealer, and explained the problem, got that look that says he doesn't want to look at it dummy! Later picked it up and was told I was problem, I must be doing it as mechanic says it is all good. and got told if it ain't doing it when you bring it in we wont find it unless it gives code! Left dealer but made sure display was at a known reference point. Later I saw it was at a different display again, so I did something you don't do often, got the manual out and read up on this. I leave the display on the economy setting just to see how It is doing and as a reference. Well it did do it and over time got worse! But not often enough to get the sound of "If it ain't doing it when you come in we won't find anything" I tried bumpy roads, hitting steering wheel, left turn, right turn, bump and turn, even took two boxes and taped over the switches on steering wheel. (Keeps the ghost out) anyway still changes, random and even saw it do it when shutting off, just as i pushed off button! Didn't repeat so dint take in.7,000 miles and dealer still says it must be me as Mechanic says no problems. But now read on as more ghosts appear!

2. DEF fluid, it is going someplace, that I know as I am feeding it to my truck and it keeps drinking. First incident was in Oklahoma, stopped, fueled up and filled DEF tank. Headed down the road and after Liver and cheese sandwich, singing to my self (about 100 - 120 miles) this thing called a Information display announced "DEF getting low" so I looked to see next fuel stop, and let the DEF display on, which said 4 green boxes above the empty (There are 8 boxes on display) My mind thought why and my analytical side said may go to a detail mode that shows more boxes before empty??? (Which I don't think it does) anyway 28 to 35 miles I watched one light after another go out as i pulled into the station. It took 6 gal to fill bought 3 of the blue Platinum, 2 full ones = 5 gal and about another gallon of the third. Now being a new to diesels guy thought this must be a "REGEN" ? which I have only seen displayed once since owning at around 400 to five hundred miles. I reading the manual again, and asking around i have been told that with only 8,000 miles on the truck, that my 17 to 19 gal of DEF fluid is high. (in history I had a check engine light and service message come on and stayed on two days then just went away, dealer I I stopped at said no codes, about 3,000 miles) Now in all this time I got a check engine light and service message again 7,000 miles, so took to dealer and in keeping truck for two days they couldn't find the reason but codes showed fuel heater! (BTW dealer said ck engine light was off next morning but showed codes, service light still on) ordered parts and to take it. (Four days of driving and service engine display stayed on the 4th day the service orange light came on. What happened next is combined with number 3 below.... Dealer replaced parts and i am again driving... I was told they have no explanation for DEF, and there is no gauge in DEF tank. ( So how does it know when getting low?) and why would that affect usage?

3. OK, what is next is mixed in with what you read above. On the road again with service message still on waiting for parts i went out to start truck and hit the switch, engine turning over and over and over, not starting and knowing something was wrong, hit the button again and kept cranking, seemed like at least 10 to 15 seconds and stopped on it's own. waited a few minutes and thought should i try again? I did and cranked for at least 5 to 8 seconds and started! whew, I took off and all seemed OK. stopped was in on business about 2 hours and came out and trucked cranked for again at least 5 seconds and started. good to go? well few miles latter stopped at Starbucks, came back out and engine started as normal! Put in reverse and camera came on, put in drive and took off. Few thousand feet and camera in back still on. I wanted navigation so I hit the home button, nothing, at 1/4 mile or more it switched at some point to front camera so i looked and found a turn in stop point at about 1 mile camera still to front and turned off truck. restarted and waited until all the screens settled. Put in reverse backed out and drive camera switched to front, driving again and seemed ok as camera went off about 1/4 to 1/3 mile navigation on.. I am good? Nope pulled up and in traffic and screen switched to front camera. I am watching traffic as i want to get off highway and check this out,when i noticed orange light in right mirror say vehicle there , but there wasn't any there in mirror glanced at left and orange light on, no cars either side so moved off road and as i stopped i saw center display changing screens like a deck of cards. Ok truck is now giving me the willies! took to dealer they put in parts and said no codes no problems, could not explain DEF usage said maybe part replaced. could not duplicate cranking so said no problem, said camera s OK not a problem so basically looked at me like I was an idiot and truck is OK.

4. Now i am at the point of TRUST, do you trust a life in a truck that does weird things? doesn't leave a trail, and makes you feel like no one believes you these problems happen?

A. Cranking has occurred now three times in life of truck, last time it happened after parts replaced!

B. center display has acted up since beginning, changing on its own, and the weird time it just kept changing.

C. display not going off, locked on camera and or screen getting frozen on a certain display. once on cameras, once on apps, twice on phone screen. Finally was close to dealer and they got to see stuck screen and no touching or button combination would change it. (Waiting to hear form service manager)

D. High DEF usage? or is it normal? since beginning.

F. Center information Display going off twice with second time going off and back on after 15 to 30 miles, then off, but still random screen changes.

G. last but not least is Trans temp. Something i don't normally look at if not towing. First time i saw was flat road and was changing screens it was at 260 i was at 75 and temp outside was at 85, i watched it drop to 170 after 30 miles and stayed that way for about 50 miles and stopped watching. Next time was at outside temp of about 70 75 degree, trans went fro 195 to 280 for about 10 miles and started dropping back to 165 then up to 195 then back to 165... don't watch it all the time but was told it was good and not outside of specs... My question why such a big fluctuation? and why change at all when not towing?

So HELP,!!!! anyone else seeing odd things like this? How do you trust a vehicle that does this? Am I over reacting? is it a ghost? And my final question is what if something in the communications system, computer, was to go haywire? could it cause a situation that could cause an accident, loss of life and no one would ever know as the mechanic always says "Looks good, NO problems, NO codes" Sorry for length, but tried to keep it brief and still tell most of the story! every few weeks it seems like something new shows up!

Edited November 22, 2020 by Steve.S

Colossus · November 22, 2020

Trust is earned, not freely given.

JimCost2014 · November 22, 2020

Am I crazy? are there ghosts?

Yes X 2. Way too much to read, so I will "cherry pick" this part to answer.

Colossus · November 22, 2020

My suggestion- Reboot the thing and start over! Take the battery cables off, leave them off for an hour, then touch them together (to discharge whatever power is left in the system, no it will not shock you unless you have 2 batteries and the other is still hooked up) then reconnect the battery cables, start her up and see how she does now. Keep a written log as well, noting what is happening, when it happens under what conditions.

JimCost2014 · November 22, 2020

1 hour ago, Steve.S said:

Sorry in advance for length, but several problems and have not shared everything about them!!!!

Am I crazy? are there ghosts? is any of it real? and it all leads to trust! I know new vehicles have a lot of electronics and they are harder to track down when it only happens occasionally. To me it is the most frustrating to go to the dealer and say this happened, I heard this, the truck did this! and they come back with "Mechanic checked it out thoroughly and everything is OK!" You drive off asking yourself did I really see this? did I do something? did I hit a switch I shouldn't have? The dealer tells you "If it is intermittent, unless we see it here, we cant fix it"   And now my Problem, search for help, and seeing if anyone else has seen this?

1. 2020 GMC Sierra Denali 2500HD 6.6 Duramax Diesel. (Which driving off the lot I was so happy about) at about 200 miles I was diving around and noticed that the display in the cluster changed! I thought it was something I did and kind of ignored it. At 300 miles took it to the dealer, and explained the problem, got that look that says he doesn't want to look at it dummy! Later picked it up and was told I was problem, I must be doing it as mechanic says it is all good. and got told if it ain't doing it when you bring it in we wont find it unless it gives code! Left dealer but made sure display was at a known reference point. Later I saw it was at a different display again, so I did something you don't do often, got the manual out and read up on this. I leave the display on the economy setting just to see how It is doing and as a reference. Well it did do it and over time got worse! But not often enough to get the sound of "If it ain't doing it when you come in we won't find anything" I tried bumpy roads, hitting steering wheel, left turn, right turn, bump and turn, even took two boxes and taped over the switches on steering wheel. (Keeps the ghost out) anyway still changes, random and even saw it do it when shutting off, just as i pushed off button! Didn't repeat so dint take in.7,000 miles and dealer still says it must be me as Mechanic says no problems. But now read on as more ghosts appear!

2. DEF fluid, it is going someplace, that I know as I am feeding it to my truck and it keeps drinking. First incident was in Oklahoma, stopped, fueled up and filled DEF tank. Headed down the road and after Liver and cheese sandwich, singing to my self (about 100 - 120 miles) this thing called a Information display announced "DEF getting low" so I looked to see next fuel stop, and let the DEF display on, which said 4 green boxes above the empty (There are 8 boxes on display) My mind thought why and my analytical side said may go to a detail mode that shows more boxes before empty??? (Which I don't think it does) anyway 28 to 35 miles I watched one light after another go out as i pulled into the station. It took 6 gal to fill bought 3 of the blue Platinum, 2 full ones = 5 gal and about another gallon of the third. Now being a new to diesels guy thought this must be a "REGEN" ? which I have only seen displayed once since owning at around 400 to five hundred miles. I reading the manual again, and asking around i have been told that with only 8,000 miles on the truck, that my 17 to 19 gal of DEF fluid is high. (in history I had a check engine light and service message come on and stayed on two days then just went away, dealer I I stopped at said no codes, about 3,000 miles) Now in all this time I got a check engine light and service message again 7,000 miles, so took to dealer and in keeping truck for two days they couldn't find the reason but codes showed fuel heater! (BTW dealer said ck engine light was off next morning but showed codes, service light still on) ordered parts and to take it. (Four days of driving and service engine display stayed on the 4th day the service orange light came on. What happened next is combined with number 3 below.... Dealer replaced parts and i am again driving... I was told they have no explanation for DEF, and there is no gauge in DEF tank. ( So how does it know when getting low?) and why would that affect usage?

3. OK, what is next is mixed in with what you read above. On the road again with service message still on waiting for parts i went out to start truck and hit the switch, engine turning over and over and over, not starting and knowing something was wrong, hit the button again and kept cranking, seemed like at least 10 to 15 seconds and stopped on it's own. waited a few minutes and thought should i try again? I did and cranked for at least 5 to 8 seconds and started! whew, I took off and all seemed OK. stopped was in on business about 2 hours and came out and trucked cranked for again at least 5 seconds and started. good to go? well few miles latter stopped at Starbucks, came back out and engine started as normal! Put in reverse and camera came on, put in drive and took off. Few thousand feet and camera in back still on. I wanted navigation so I hit the home button, nothing, at 1/4 mile or more it switched at some point to front camera so i looked and found a turn in stop point at about 1 mile camera still to front and turned off truck. restarted and waited until all the screens settled. Put in reverse backed out and drive camera switched to front, driving again and seemed ok as camera went off about 1/4 to 1/3 mile navigation on.. I am good? Nope pulled up and in traffic and screen switched to front camera. I am watching traffic as i want to get off highway and check this out,when i noticed orange light in right mirror say vehicle there , but there wasn't any there in mirror glanced at left and orange light on, no cars either side so moved off road and as i stopped i saw center display changing screens like a deck of cards. Ok truck is now giving me the willies! took to dealer they put in parts and said no codes no problems, could not explain DEF usage said maybe part replaced. could not duplicate cranking so said no problem, said camera s OK not a problem so basically looked at me like I was an idiot and truck is OK.

4. Now i am at the point of TRUST, do you trust a life in a truck that does weird things? doesn't leave a trail, and makes you feel like no one believes you these problems happen?

      A. Cranking has occurred now three times in life of truck, last time it happened after parts replaced!

      B. center display has acted up since beginning, changing on its own, and the weird time it just kept changing.

      C. display not going off, locked on camera and or screen getting frozen on a certain display. once on cameras, once on apps, twice on phone screen. Finally was close to dealer and they got to see stuck screen and no touching or button combination would change it. (Waiting to hear form service manager)

      D. High DEF usage? or is it normal? since beginning.

       F. Center information Display going off twice with second time going off and back on after 15 to 30 miles, then off, but still random screen changes.

       G. last but not least is Trans temp. Something i don't normally look at if not towing. First time i saw was flat road and was changing screens it was at 260 i was at 75 and temp outside was at 85, i watched it drop to 170 after 30 miles and stayed that way for about 50 miles and stopped watching. Next time was at outside temp of about 70 75 degree, trans went fro 195 to 280 for about 10 miles and started dropping back to 165 then up to 195 then back to 165... don't watch it all the time but was told it was good and not outside of specs... My question why such a big fluctuation? and why change at all when not towing?

So HELP,!!!! anyone else seeing odd things like this? How do you trust a vehicle that does this? Am I over reacting? is it a ghost? And my final question is what if something in the communications system, computer, was to go haywire? could it cause a situation that could cause an accident, loss of life and no one would ever know as the mechanic always says "Looks good, NO problems, NO codes" Sorry for length, but tried to keep it brief and still tell most of the story!   every few weeks it seems like something new shows up!

I guess my real question to you is, does it really matter if someone else has the same problems as you?

They are going to have their thoughts on fixes, or complaints on the truck they have.

It sounds like you have an expensive truck and are not happy with it, open a claim with GM if you are not happy with your dealer, they did not make it, they are just doing a crappy job fixing it in your eyes.

Let GM know what is going, do not let the dealer you are doing this, or go to another GMC lot, you are not tied to the one where you bought it from for warranty work.

The answers you get from the forums will not fix your truck, and if you try to do the repairs, you will void your warranties, use them, that is why most of us buy new trucks, to not to have to work on them ourselves when they break.

Trucks are a machine, they will break at one point no matter who made it.

Steve.S · November 23, 2020

I agree, with not finding proper fix on here. I was more curious to see if anyone else had similar problems so i don't think it is me although (I am pretty sure it is not). I have talked to GM about the random system problems. they are looking into solutions and ways to handle them. I like the truck, just upsets me that dealers will say "If it doesn't leave a code, and it is not something that shows up wen don't have a remedy. cars and trucks rely on to much computer control and computer diagnostics! I understand it's not the mechanic at fault as they have get an error code to just replace parts! which at times seems like a customer doesn't get the care they think they should. I do have a case with GM and it was mentioned that there is a chance they will do a buy back. which if it comes to that, i would take, but, during recent conversation with GM they asked if I had heard or seen this type of action with any other trucks or owners.... Having worked with GM on another truck, (8 speed trans problems) I know they don't just jump up and say lets swap vehicles. Thanks for the reply and i will stay on top of finding a solution.....

JimCost2014 · November 23, 2020

1 hour ago, Steve.S said:

I know they don't just jump up and say lets swap vehicles.

No, they do not, but they will if you can prove to be an upset customer with a valid complaint.

My 14 K2 ended up being a "trade allowance", which put me in my 16 K2, which ended up being a full blown buy back, which put me in my current 18 K2.

It is a long grinding process, but can be done.

And, you are very welcome, good luck in your quest to get things resolved.

Happy Thanksgiving!!!

Edited November 23, 2020 by JimCost2014

Dennis C · November 24, 2020

hello steve this dennis c. I am having the same issuses . my friends think im crazy talking about them. contact me at this email. lets talk!!!

TheGeek · November 24, 2020

My cameras messed up a few times and I just select the music icon. I actually like it when the cameras mess up at the car wash, you see all the rollers and brushes. As far as stopping for a few minutes, don't turn your tuck off. That is probably the worse thing you can do with a diesel.

Steve.S · November 27, 2020

UPDATE;

Well since dealer didn't want to do a "Reset" I went ahead and did it. removed battery cables, and just let it sit over night, Next morning took the Positive (+) and Negative (-) cables and put them together. (This draws in energy from the system and makes sure it is all flay. You can normally do this in a shorter period of time, but i got a lot of it! haha anyway I went in got coffee, did a little searching for new goodies or about 1 hour. Cleaned the ends and applied some good electrical grease and reconnected, crossed my fingers and turned the truck on. Checked the gauges and set them to a spot. (To see if they change again) Turned the truck off and let it sit for a few minutes. Pressed the Brake pedal and Hit the button. Truck turned over for about 7 seconds and no start. Hit the button and let sit for maybe five minutes while I rechecked everything I had done. Nothing was out of the norm so back in and pressed brake hit the button AND YEAH about 2 or three turns and crackled to life. let everything settle and just observed then went thru and did any missed setups, just like new! off on the test drive so trans could relearn and make sure all is well. #0 to 45 minutes of driving and all is well, so headed home. about 1 mile from the house and Check Engine light came on. #%^&&# truck, now what. pulled into house and thought take to dealer, but first wanted to see what code was thrown. Hooked up the tester and it said no codes, but yet I am staring at a orange light which I know means something should show. went in the house and stewed, then out to the dealer.. Truck started norm and light on I was headed off to dealer and want answers. back out of driveway put in drive and within a foot of moving Ck engine light off. Now as always if I go to the dealer and ask to check for codes they don't want to if light is not on. told them what i did and tech said he would check and if code was there they would write it up for what it shows. NO CODES, same as what i saw.... NOTHING.. A day of driving and all went good until next morning truck would turn over for 15 seconds and stop on its own no start... so i called and asked for tow truck, which they said would be about two hours.... an hour latter I thought i would try again as if it got there and started I would look like an idiot.. It started on second or third revolution so I am an idiot canceled tow and decided until it breaks all the way just live with it.... I do have a GM case going so called and explained what happened and was told they noted it and said if it does it again take it in.... Just wanted to update n the crazy thing