I started my wife's 2007 Avalanche up last night to move it and it has a very loud ticking noise coming from what sounds like under the passenger side of the engine. I revved it to see if the ticking would speed up with the engine and it did. First time I tried it however, there was a delay and then a pop. My brother said it sounded like piston slap to him. I recorded this video I'm hoping someone can help me out here. Oil pressure is about 55 and all the other gauges look good. No lights on.