I have a 2008 GMC Sierra Denali 1500 with 130,000 miles. I know that it’s not brand new but I have only owned it a year. After a few months of having it, it started acting crazy! Lights flash on and off, radio goes on and off, all the lights on the dash come on at once, doors lock and unlock continuously, it loses all power at any given time, and it breaks on its own at any given time, I have had more than my fair share of close calls, driving 70 down the expressway and the breaks slam on all by them selves, lights going completely dark late at night... I have had it looked at more times than I can count and no one can ever find what’s wrong with it or what causes it to do this. I have replaced the alternator, and the battery cables and it’s back to doing the same thing. GM says it’s not a common problem, but if you look online thousands of people are having the same issues. GM says it’s something I did and just a coincidence that other people are having this issue. I know it’s not a brand new truck but it’s new to me and I paid a lot of money for it. I just want it to run right and be safe for me and my family to get where we need to go.