I’d try the two but trick. Btw, it’s not a sending unit. These engines are notorious for sludge. Do a Google search for it. You’ll get good at dropping the pan and cleaning the oil pickup before you sort it out. Run Wal-Mart conventional oil with 20% marvel mystery oil and change every 3k. You might also pull the oil press sender and clean it. A full de-sludge is no job for amateurs, but a gradual cleaning should get you by.
Two nuts together trick. Damn autocorrect.
I did the google search on the 1MZ-FE and Sludge and u suggested, and I discovered you are right —the sludging is apparently a very broad problem.
For the 3k mile OCI’s what conventional oil subtype should I use with the 20% Marvel..?
20w-50...? I need something thick.