I was wondering if anyone here has a vehicle that is driven very little and does long intervals with dino oils, I have a 1987 mazda B2000 that is driven about 5 or 6 thousand miles a year, 6 month intervals is about the max for me, so far.
When I was using Dino I was very successful with 3000, or 7500, depending on owner's manual without regard to time. If it took a year, it took a year.
I now use Mobile one with the same plan. Only it's 5-6000 miles no matter how long it takes. My 78 Ranchero took 2 1/2 years on one OCI. Still runs great with 190240 miles on it.
I have one vehicle that I only put on a couple thousand miles a year. It has dino and I change it once every two years regardless of miles. Usually less than 5K miles. Each time it is run, it is run long and hard enough to burn off any condensation so I don't worry about it.
I do 1 year OCI's with my project car. I only drive it in the summer(3-4k miles) and use Castrol GTX and a Motorcraft filter. The oil looks fine when it comes oil.