I own a 2004 Toyota Sienna and have used standard Pennzoil multiviscosity oil for all service to date. The van now has ~75k miles and I am posting to ask if there is any true benefit to change to Pennzoil’s oil for high mileage vehicles?
Not really. This oil is made mainly for old engines that often have leaking seals. If your car does not leak, you don’t need this oil. A 2004 Sienna with only 75,000 miles should be in essentially new condition, if well maintained. Just keep doing what you are doing and start worrying when you reach 200,000 miles.
And the leaks your Toyota v6 will likely develop (valve cover gasket and cam seals) probably won’t be solved by the high mile oil, at least not in my experience.
I’ve owned many vehicles over 300k miles and NEVER used this oil…and never had a problem. Just keep using the oil that got you there and you’ll be fine.