acdac21

Thank you. I'll start pulling plugs and looking at them this weekend. I have the luxury of working remotely, so I shouldn't have any reason to drive my truck before having a chance to look at the plugs. Any idea as to why it only runs poorly when I put it in Drive and am sitting still?

Good morning, I'm new here, so please forgive me if I'm not doing this correctly. I have a 2009 Silverado 1500 4x4 Z71 with 5.3 Vortec with approximately 117k miles. It's burned oil ever since I've owned it (bought it with 68k miles on it). I noticed it idling very rough over the last couple of days, but it only does it when in Drive and stopped; it runs fine when I'm actually driving it, or when it's in Park/Neutral. It has always had a slight shudder, in park/neutral, but nothing like what it's doing when in Drive and stationary. I did notice that it was a quart low on oil a couple of days ago, and I filled it to the fill line, but a quart low isn't going to cause this problem. Any ideas what might be wrong? To my knowledge, my truck has original plugs, coils, and wires. The transmission has a slight slip in 4th at lower speeds, and has since shortly I after I purchased the truck. Just trying to give as much background info as I can. Thank you!