2002 dodge 4.7 Engine sludge
OK here is what I know as I have a 2000 Dakota with the 4.7. The oil fill tube is actually the highest part of the engine an all the crank case vapor (water) builds up at that location. Dodge had a service bulletin out and was to replace the oil filler cap when customers filed a complaint with the dealers. So I would suggest going to a local dealer and ask about the supposed new and approved cap. I just change me oil and have 220,000 miles on my truck with no issues.