1999 Dodge Durango oil burning

I have 318 ci. engine in my durango and it buring oil. I use a 0-30 oil in my engine since it has a lot of miles on it. the oil was burnig through my engine but it never made it through my exhaust. After a while, my engine started knocking because the oil was getting through the plenum gaskets and into my spark plugs so i replaced the spark plugs and all of the gaskets. i also replaced the oil and oil filter with the same grade and it ran fine for a month and a half. Then my oil gauge lost pressure and turns out i had no oil. The oil is obviously burning off again but its still not through the exhaust. Where could the oil be burning now and how do i stop it? thank you