I have a 2011 Sierra with a 5.3 - 50,000 miles and it is intermittently starting. I know this is a common problem with these trucks and I have read about replacing starters, remotes and spending crazy amounts of money to no avail. I have also heard of the shake the truck cure, the depressing the parking brake cure, keep turning the key and on and on .... Does anyone know what is really going on? Today was the second time it would not start. Here is what i noticed today. First it started fine at about -15 this morning and I drove to work. When I got to work someone told me my backup lights were on. Given I had to much to do at work I disconnected the battery and returned hours later and reconnected the battery. Same problem with the backup lights staying on but now the truck won't start, turn the key and everything but the starter works. After doing some of the cures outlined above I turned the shift knob from 'auto' to 4 x4 high - turn key, nothing but then I turned it to 2 wheel drive and eurika! It starts but the backup lights are still on. I drove home about 30 miles cursing the truck and then I find the backup lights have gone out, the truck starts under various settings ...no problem everything is cool .... until the next time .... any ideas would be greatly appreciated. I do not want to get stuck given it will get to -30 here over Chistmas.