I don't know if you read it, just throwing this info out, but I think my crank is lobing. That's why I'm wanting to do something with the engine, I think I might wait for tax season, get a secondary vehicle and then either wait for the Yukon to give and repair it or just start fixing her up once I get a secondary vehicleTo the OP, if you want to get bang for the buck... leave the engine in there, do a 4L80e swap, swap the factory "posi" out for a good aftermarket unit, and build or buy a cheap turbo kit. I will posy a video link to a Yukon XL that makes 450ish at the tires with a STOCK 5.3 and a turbo kit. He probably makes more but at the time of the video he didn't know that it was AWD so he was burning up the transfer case on the dyno.
Uncle Rob Yukon XL 5.3 dyno