CRApex

Switched over to GMC..2026 AT4 HD 3500, needed a different look after a having Chevy's for years.

Thanks..yea I tried that. Its more of an annoyance than a real problem but frustrating nonetheless. A couple times when it has booted the Sirius XM favorites don't show up, just shows "Hold" to save the channels but then upon a second reboot they load but end up in a random order vs. how I had arranged them..again..frustrating.

So does anyone have a sloution to the infotainment losing audio upon startup? Mine cuts out for a second (does it 8-10 times) after starting the truck. My buddy's does the same. I have had a software update done at the dealer and it actually seems worse after that.

If you love the Duramax and are hesitant about the gas, stick with the diesel. I went from a 2021 HC Duramax 3500 and convinced myself the 6.6 gas was the way to go, I'll just say that's a tough transition to make. I'm back in a Duramax again. There is soo much more power with the diesel, not saying there is anything wrong with the gas, just don't under estimate the power difference. As far as reliability...I can appreciate that and agree that over many years of ownership the gas will be more reliable, something I've personally decided isn't worth it given how much more I enjoy driving the diesel. I've had excellent luck with the diesels on the reliability side as well...maybe I'm just lucky??

Mine does the exact same thing. I took it in and they did a software update that did not fix it. It only hapeens the first 3-5 minutes after starting the truck.

You nailed it. I've had diesels for years and the only issue I've had was the DEF heater recall on my last one. I've also used them for plowing which is a significant amount of time idling with obvious stop and go without an issue. That said, I won't push my luck and keep one past the 100k warranty. The trade value will get you back a chunk of that extra 10k option price too. Maybe we've both been lucky.

Are you still driving the truck in your signature? (2021 Trail Boss) If so, that is different from the 24 and up HD's, I believe it would also be different from the 2023 and up 1500. On the 2021, I would just tap the fuse labeled for High beams in the fuse block under the hood.

I found the same thing...Had a 2024 with the 6.6 gas, great truck but underwhelming in the power department. I switched from a diesel when they added the 10spd thinking it would bridge the gap. Bottom line, I'm back in a diesel. Not saying the gas is a bad truck, it gets the job done but man, it is slow.

The 3.5 can create HP and torque but will not come close to outliving that 6.6.

Also, I inserted the wire into the rear of the plug, to avoid any damage to the existing wire.

That makes sense. My setup has worked well with no issues.

Correct, that is the wire I tapped.

Not sure if its PWM but I can say it triggers the relay just fine. I'm taking a chance on it causing an issue with the LCM but so far it has worked flawlessly and not caused any issues. I did not find which wire goes to ground from the high beams, probably the safest route if you can track it down.

So I found a spot to use as a trigger for the lightbar relay. Its the white wire coming out of the lighting module under the steering wheel. Its the smaller module that's in front of the larger one. I plugged a wire into the connector and ran it to the engine compartment and connected to the relay as my trigger, the light bar now works with the high beam switch. Its been about 3 weeks and so far, no issues.

The 1500 has a different transmission than the HD, its not the Allison branded version.