I was thinking of changing my oil over to the new synthetic stuff. I drive an 03 grand caravan with a 3.3ltr engine. The first question is 1) al lot of people are saying to go to 15w40 rather than the 5w30 that is presently recommended when using regulare oil. Has anyone been using 15w40 synthetic oil and had any problems with it. 2) The reason I would like to go to the synthetic oil would be to increase the mileage between changes but I have been doing some reading on the net and some articles suggest that the usual oil filters you buy in Canadian Tire or Wal-mart (fram etc) only actually filter oil for about 4000km and after that I guess the oil just passes right through them unfiltered. Are their recommended oil filters out there that one should use when using synthetic oil. I don't see the point of changing over to the better oil if the filter is not going to be the weak link?
Bill