Offcamber

2016 GMC Sierra 6.0 4WD about 36K on the OD. First let me start that for years I have had this very intermittent no start issue which I am convinced is the starter or the wiring harness....Battery power is good, hear the solenoid click but starter does not turn over. The solution was to crawl under the truck and smack the starter with a wrench and the truck would the start. I have planned to just replace the starter as I figure there is just a dead spot. However it so rarely does it and this truck sits a lot I just haven't got round to it. "lazy" The other day I had tires put on ( don't think this is relevant but figured I'd mention it.) They did it in the parking lot with floor jacks so I doubt my current issue has anything to do with that. Anyway the other day I went to move the truck and no start again. Since I didn't really need it and it was raining I figured I would just leave it for the time being. Today I went ( outside temp is much warmer today) to start it and it fired right but then the dash lit up with almost every light. All kinds of transmission codes back up camera didn't work engine ran kind rough no ABS or TC. Threw the scanner on it and you can see the diagnostic report below. I figure all these modules can't fail at once...So it sounds like bad ground somewhere. Everything is good at both batteries. Shut it down restarted and everything cleared. Took it to get gas with no issues. So my questions is where is the best place to start looking for a bad or loose ground?? A buddy has a lift so I am going to try and get up under there and probably replace the started while I'm there. Thanks

So second key made no difference I was going to disconnect both batteries and see if that reset things. I tried resetting the program a few more times. Then it started going all the way down instead of up. Reset it again and it moved less down then reset again and it seems to say put. So I don't know what the issue is. I'll keep an eye on it and see if it starts doing it again. It seems like the mirror lost its point of reference.

I haven't tried the other key but I will thanks.

That was going to be my next step. Everytime I turn the key on it tilts all the way up. I have tried resetting the program but still does it.

Thats what I was thinking. The truck has had a few electrical gremlins. I'll check the connections and see if I can fix it. I really don't want to replace the mirror.

Yes it's done while driving.

My passenger mirror has started moving on its own. Truck has 29K miles on it. No factory warranty. I do have an extended warranty but I just used it yesterday to have a check Engine light fixed O2 sensor) and the horn replaced. Today I am driving along and the mirror just goes all the way up and out. I move it back and it stays fine but when I start the truck it goes to the extreme range again. Tried resetting the seat preset and turning off the curb assist. Any idea what's causing it. I really hate to bring it back in to the dealer for this. I fold the mirrors regularly ( power fold) and that works fine. I am wonder if its a faulty/dirty connector or something.

As stated, I know they are not the same suspension however its possible something got loose like spring shackle...I don't know like I said probably not relevant.

This may be of no help. I had a similar problem with a Jeep Wrangler many years ago....I had it aligned, checked re-checked still would get death wobble. By luck I found the problem. My rear track bar was loose, causing the rear axle to shift just enough to throw the alignment out and cause the wobble. Now I know that a Jeep is very different 1 ton duelly but maybe my experience has some relevance? Probably not

I Gas or diesel?

I read a lot of this thread, and although I do not believe I have the problem I do notice more play in the wheel than my 1500 did. Considering the suspension and geometry is different this doesn't surprise me. My question is.... Has anyone had this issue on a truck other than a crew cab and or not built in Flint? Sorry if this has been covered already.

Wow my 03 Dodge 2500 5.7 pulled like crap. Always hunting for gears revving high to maintain speed on hills. this was pulling a toy hauler max GVW of 7500lbs. Bought a 1500 GMC 5.3 and it pulled so much better, The only thing the Dodge had over the GMC was weight. It just handled the trailer better but that was to be expected as the Dodge weighed a lot more. Now I have a 2016 2500 6.0 and I haven't towed the toy hauler with it yet but I am sure it will pull better than the Dodge did.

If you use regular grease you run the risk of shorting out everything. Has to be Dielectric. You ave to use dielectric grease or you will short everything out....As stated keeps moisture out and contacts clean.

This happened to me on my 1500... Usually just making sure the plug is all the way then you need to shut the truck down and restart. This should rest the system so the truck detects the trailer fully. You can get light and no brakes.

On my 1500 I had ti happen once....but it was my fault I had not put the plug in all the way...I realized this when my trailer lights weren't working. Got out of the truck to check but did not shut the engine off.....I realized I had no trailer brakes pretty quickly.7K lb load on a 1500 you know if the TB aren't working. Stopped shut the truck off and restarted all came back up and rode two hour home no problem. As for stabilitrac....don't discount it to quickly. It saved my ass on the highway once. Same 7K trailer.....highway speed 70-75mph came around corner there was an accident off in the median and the idiot in front slammed his brakes on (not necessary as everything was off the road) and had come to almost a complete stop. I'm not sure I would have stopped in time or maintained control without the tuck doing its thing. YMMV