I wish it would be that simple. I replaced the valve covers, gaskets and pcv valves about 2 months ago, right after I did the headers, so less than 1500 miles on them. The valve cover on bank 2 didn't really keep the oil in that well! I am afraid my problem will be more sinister than that, and far more expensive too. I am already pricing rebuilt heads and possible an engine swap. The only thing I can think of that would make it burn oil is bad valves or seals/stems or bad rings. Bad rings would mean another engine. Not too happy, it has cost a lot to do all this work so far. I am into the vehicle for about 6k all total. 4K for the truck, new headers, b pipes, tune, valve covers, plugs coils injectors. And only 162k miles?!