My 2019 Toyota Tundra has a required 5,000 mile OCI because it is the Flex Fuel (FFV) engine. Even though I don't run E85 in it ever, which means I can probably do 10,000 like the non-FFV Tundras without issue, I don't want to void the warranty. Anyway, my free Toyota Care oil changes are ending soon, and my dealership uses bulk Mobil Super Synthetic for the oil changes, but now I will be paying for it. Should I just let them continue to use that oil, or should I bring my own? If I bring my own, they will only charge me labor for the service. I was thinking for only a 5,000 mile OCI that Quaker State Ultimate Durability might be a better choice. When I get out of warranty, I plan to do 10,000 mile OCI's with Mobil 1 EP. Until then, I would greatly appreciate your opinion. *P.S. Would change it myself, like I did when I was younger, but I have rotator cuff tears in both shoulders and suffer from vertigo.