Crankcase (pcv) problems of the 2005 Jeep Grand Cherokee

Oil changed routinely around 3000 miles. Cold morning -3 fahrenheit. Let car warm up for 5-10 minutes. Drove 5 miles to work. When stopped at a light on the way to work I could smell hot oil. I thought it was the car in front of me. After I parked in the car I noticed a large amount of smoke coming from my hood. I immediately popped the hood to see what was going on. There were approximately 3 inch tall flames on the exhaust manifold for about 6 inches along the manifold. Since the engine was off the flames died out and did not ignite the car. The valve cover gasket had failed and was leaking oil out on the exhaust manifold. Dealer thought the pcv valve might have had moisture in it and froze. This caused excess pressure to build and popped the valve cover gasket the weakest point. Dealer replaced valve cover, valve cover gasket, and pcv valve. Failure again: exactly 2 weeks after the first failure. Same scenario, it was 3 degrees this time and I let the car warm up for less than a minute. This time though there was no fire. Dealer tore deeper into the engine and found the oil had sludged up. I had just changed my oil a month ago and 1000 miles previous. The sludge caused moisture to be trapped in the pcv valve and freeze. The sludge also was found in every component the oil lubricates. When I asked the dealer what I can do to prevent this from happening again they told me to change my oil as recommended. I already do that. They suggested that since I first saw this failure at 35000 miles, I should have my engine torn apart every 35000 miles to have the sludge removed. They told me they have seen the sludging problem before and Chrysler is aware of it. Chrysler will not cover the sludge clean up once it is out of warranty at 36000 miles.