I purchased the car used with 20k miles on it. It now has about 65k miles on it. During this time period, I have only used Mobil 1 5w30 and a Purolator PureOne filter in it, changing both every 5000 miles. However, I've noticed over time that my lifters are noisy, and was told recently that the Mobil 1 may be the cause, or at least switching to an oil like German Castrol 0w30 or Amsoil SSO 0w30 will help quite it down. Any thoughts on this? Would running any of these oils pose a problem for my car? I live in Upstate NY if that helps.