Just wondered if any one has run across having changing oil Moble synthetic 5-30 in a 03 LS 3.9 on cold starts and I live in Hawaii there is a horrible bearing sounding rattle for just about 2-3 seconds then gone all day till about 8-10 hrs. of sitting and it does it again. 107,000 MI. just happened right after oil change . Not like this was slowly coming on . Just came on. Sounds real bad for those couple seconds then runs great other than all the other problems I read about on this Forum. Anyone use additives like Lucas . Getting ready to change oil. Thanks in advance for any help.