does the GM 5.3 engine have lubrication problems at the valve area?
Not sure what you mean by lubrication at he valves. Your 5.3 is a direct injection engine that squirts fuel directly into the engine without passing by the valves. That means the fuel doesn’t wash off deposits that can collect on the valves. Not really a lubrication problem, more of a EGR deposits problem. For that reason alone an intake clean with BG products or Seafoam or similar every now and again would probably be a smart idea.