Hi Iam a newbie here and see from all the threads you guys know your stuff! Quick question: I have a 99 explorer with a 4.0L SOHC motor 38k miles and on my last oil change made the switch to 5-30 M1. I have about 300 miles with the fresh oil/filter and had planned to change the filter to handle whatever sludge was knocked loose. From reading other posts this may not have been the best idea, the thought of sludge clogging my oil passages has been haunting me. Do you guys think I will have problems? After how many miles should I change filter? Or what should I do? Thanks guys