Not again...What the heck GM? UPDATED AGAIN Dec.12

[426ted]

Well here's another one. Driving down the highway when the truck suddenly loses power. Takes me a sec to realize the truck isn't running. DIC warning 'put shifter in neutral and press start button'. Nothing happens. Manage to strongarm and stop this beast in the center of the highway (middle turn lane so somewhat safe). Put the truck in park and tried the ignition. Engine turns over but will not start. Phone gets the text below. I really do want to love this truck, but I think I got a lemon. Three times prior speed restricted with the last fix a replacement throttle body. And now this. Towed to the dealer (though out of range so I am on the hook for the extra distance not covered by the warranty). Funny that the first truck couldn't take it as the electric park brake engaged as soon as he put it in neutral. Had to call a flat deck. Or so he told me- I took an Uber home long before. Anyways, thought I'd share another fun experience that I have had with my truck.

Edited December 13, 2025 by 426ted
Updated

[Homer1959]

13 hours ago, 426ted said:

Well here's another one. Driving down the highway when the truck suddenly loses power. Takes me a sec to realize the truck isn't running. DIC warning 'put shifter in neutral and press start button'. Nothing happens. Manage to strongarm and stop this beast in the center of the highway (middle turn lane so somewhat safe). Put the truck in park and tried the ignition. Engine turns over but will not start. Phone gets the text below. I really do want to love this truck, but I think I got a lemon. Three times prior speed restricted with the last fix a replacement throttle body. And now this. Towed to the dealer (though out of range so I am on the hook for the extra distance not covered by the warranty). Funny that the first truck couldn't take it as the electric park brake engaged as soon as he put it in neutral. Had to call a flat deck. Or so he told me- I took an Uber home long before. Anyways, thought I'd share another fun experience that I have had with my truck.

  If your truck is covered by the 3-year, 60k warranty, check your manual—roadside assistance should cover the full cost of the tow truck as long as it’s towed to the nearest dealership. It’s different if you’re claiming under the GMPP, as they only cover up to $100.Fight my friend fight   

[426ted]

Thanks Richard. I plan on it.

[426ted]

So got the truck back today. The cause was a battery internal circuit fault. They jumped the vehicle, found a bad battery and replaced it. Did not speak to the tech, only the service tech

 

Now, don't know if I buy this. The truck has dual batteries. If it has enough power to crank over, why not enough to run all the related electric circuits.  SO I guess you all should be aware that if your battery is failing you won't get a warning other than the engine shutting off. While driving. At potentially high speeds. Thought about going another route and getting rid of this pig, but after spending Friday night researching other trucks, it seems that really no one manufacturer is better than the other- they all put out garbage at times. It's the devil you know I guess, as my Grandma used to say. 

 

If I can figure out over the next few weeks how to reduce the size of a video, I'll post one of the truck blowing blue and see what you all think. Cheers for now everyone.

[PBNB]

Did they not suggest to replace both batteries? I wonder if the second battery dropped (as low as the main battery) low enough to prevent the electronics from working? 

 

Cranking over the Duramax probably takes a ton of amperage and this could pull the voltage down enough for the electronics to stop working but this happened while you were driving which is puzzling??

 

Which dealership are you dealing with? I noticed in your signature that you are in BC.

[EXSlider400]

With all the electrical on new trucks, I recommend adding an additional grounding strap. 
 

This may help;

 

 

Edited December 1, 2025 by EXSlider400

[Pryme]

Are diesels not like gas where they will run indefinitely on a bad battery as long as the engine is running? If so, I don’t buy a bad battery causing the vehicle to shut off going down the road. 

[johnnyquick]

49 minutes ago, Pryme said:

Are diesels not like gas where they will run indefinitely on a bad battery as long as the engine is running? If so, I don’t buy a bad battery causing the vehicle to shut off going down the road. 

Unless the alternator AND the other battery is bad all at the same time...lol  which with these trucks it is all possible.

I even have to change out the blower motor at 65k  miles my kids Honda Element has 194k and everything still works.

These trucks were made as CHEAPLY as possible it seems to me but I am not whining on the internet just voicing my opinion

The truck the OP is posting about is NOT fixed and will leave him stranded again and could kill someone GM only moves when threatened with litigation by the Govt.

[426ted]

On 11/30/2025 at 2:14 PM, PBNB said:

Did they not suggest to replace both batteries? I wonder if the second battery dropped (as low as the main battery) low enough to prevent the electronics from working? 

 

Cranking over the Duramax probably takes a ton of amperage and this could pull the voltage down enough for the electronics to stop working but this happened while you were driving which is puzzling??

 

Which dealership are you dealing with? I noticed in your signature that you are in BC.

 

Dueck GM in Richmond

[426ted]

7 hours ago, johnnyquick said:

Unless the alternator AND the other battery is bad all at the same time...lol  which with these trucks it is all possible.

I even have to change out the blower motor at 65k  miles my kids Honda Element has 194k and everything still works.

These trucks were made as CHEAPLY as possible it seems to me but I am not whining on the internet just voicing my opinion

The truck the OP is posting about is NOT fixed and will leave him stranded again and could kill someone GM only moves when threatened with litigation by the Govt.

 

I agree with you that I doubt the problem has been fixed. When it died and I was parked in the center of the highway, I noted that the dash etc stayed on. Even with the truck 'off' I still had radio and display. Opening and closing the door made no difference- display was still on. I think that is what killed the battery. I told the service guy but here we are. 

 

The posts I make about my experiences are to keep everyone informed if someone has a similar situation.

[davester]

14 hours ago, Pryme said:

Are diesels not like gas where they will run indefinitely on a bad battery as long as the engine is running? If so, I don’t buy a bad battery causing the vehicle to shut off going down the road. 

way back, with fully mechanical diesel setups, I would say this is true (depending on how the fuel shutoff setup was designed), but more modern diesels have a bunch of electronics controlling them, both how the fuel injection side works, as well as the regeneration side, so if the electric power goes south, the engine will stop working.

 

Diesels are slightly less susceptible to this, as GM uses a 2 battery setup for them (I think even the 3.0 duramax gets 2), so a bad battery is less likely to take down the electrical system (it's still possible though).

 

But if the alternator is working ok, and the battery is just not holding a charge (vs say, having an internal short so it draws more power than the alternator can put out), both gas and diesel engines will just keep going.

Edited December 2, 2025 by davester

[PunchT37]

Bad batteries can send electrical "noise" through the system. This causes problems especially in these new vehicles. There are MANY modules and they don`t like the noise. No electronics do. AND, these modules are communicating back and forth with each other at all times. Many problems pop up with bad data.

 

 

 

[PBNB]

15 hours ago, 426ted said:

 

Dueck GM in Richmond

I have been dealing with the service depot at Dueck on Marine. Not sure if you want to try taking it over there?

[426ted]

So here we go again. Died again, this time doing 90 on a freeway onramp. Oh joy. Another tow back to the dealer. Finally talked to the service manager. That made me happy as I was also able to show the video of the truck blowing blue under hard acceleration. Anyways, he explained why they replaced the battery which obviously did not help. They replaced a 'fuel pump module' and will do further testing. After looking around online, it seems that every manufacturer puts out turds at times- mines just one of them. So I may as well stay with GM. Likely will take a kick in the nuts and trade this one in for a 2026. Cheers everyone.

[Pryme]

1 hour ago, 426ted said:

So here we go again. Died again, this time doing 90 on a freeway onramp. Oh joy. Another tow back to the dealer. Finally talked to the service manager. That made me happy as I was also able to show the video of the truck blowing blue under hard acceleration. Anyways, he explained why they replaced the battery which obviously did not help. They replaced a 'fuel pump module' and will do further testing. After looking around online, it seems that every manufacturer puts out turds at times- mines just one of them. So I may as well stay with GM. Likely will take a kick in the nuts and trade this one in for a 2026. Cheers everyone.

Doing 90 on the freeway onramp!!! Vin diesel filming fast and the furious: heavy duty! Coming to a theater near you. 
 

yeah I’d be trading that for sure.