I recently started maintaining a 1998 Toyota Avalon (officially recognized as a slude producer) and under the cap its dark black everywhere but has been that way for years. It has survived on the local shops bulk dino oil at no more than 3k oci for the last 10 years. With that said im a little afraid to jump in with something like PP or M1HM and risk upsetting things too much. What does everyone think of PYB and Mobil Super? Its hard to pass over the Mobil as my grandfather made his living as a captain for Mobil shipping oil across the pond in WWII so I have a soft spot for Mobil even if that sounds crazy. I just notice all this marketing where Pennzoil says they clean better than anyone and that's hard to overlook. I also learned of my 2005 Honda Odyssey needing more frequent OCIs due to similar issues and I recently switched from VWB to PP in it and when I did oil consumption doubled not enough to freak me out but enough to have to add a qt every 4k probably just switching chemistry up its the first OC with it. Any general ideas on how well Mobil 1 or Mobil Super cleans compared to Pennzoil products would be helpful as cleaning is my big priority. I really don't want to jump into specialty cleaning products and procedures it just makes me nervous.