Have an 08 Suburban with a 5.3 AFM non-flex engine with 90,000 miles. Recently it has what sounds like a noisy lifter every once in a while..... not all the time. I keep up with the oil changes religiously and add Risolene every time. So the question here is, do I have bad lifters or could it just be a bad solenoid valve on the plate? I have googled this online and have seen responses of everything from using motor flush to almost a complete overhaul........ I have read where the AFM is nothing but trouble and shortens the life of the engine by gumming it up, others swear it's a great engine...... If this is a junk motor, I'd rather just cough up the $4k for a long block ($6700 installed by dealer) or just trade this in on a real truck....... As far as doing the work, I'm very capable of that, but don't want to waste time and money doing something that is not needed


opinions? recommendations?