Morning guys. Recenlty picked up a 2007 Yukon SLT 2/wd. It was a fleet veh for the company I work for and currently it has a little over 206k miles. All highway miles so the interior and exterior look amazing for the mileage. I would like to get another year of service out of it and wanted to get some advice. So far I have replaced air filter, spark plugs, cleaned the MAF and TB and ran a tank of 93 with injector cleaner. The truck runs amazing but still has a rough idle. It's worse when in drive and braking then when in park. As soon as you step on the gas it moves great and the idle doesnt fluctuate at all, you can just feel (and see when you pop the hood) the engine shaking. It was previously taken to the dealer who said it was normal. I've done a good bit of research and seen this is a common issue. The motor is very quite with no ticking so I doubt it's lifters. For what I paid I am more than willing to just deal with it as otherwise it's great. Any suggestions?