I have a '05 Envoy XL SLT V8 5.3l and now I am getting a clunking sound when the engine revs up as well as can stall while ideling. My oil pressure is also low and rises when engine is engaged. From what I gather it is most likely the rod / bearing? My mechanic said all new engine and would be $6,600! Majority of that is for the V8 engine, honestly I do not need the bigger engine can I have them get a I6 to drop in? Or will I have to change other things then as well? I am pretty mechanical myself just put new rotors, brakes, tie rods inner and outer, as well as wheel hubs on this vehicle and do not want to have to scrap the car but can't pay $6,600 right now either any advice would be great. I am going to ask a bunch of other mechanics, for a quote in the time being. Also can they just replace the rod and bearing?