- Feb 20, 2019
The old claim with conventional oil was replace every 3,000 miles or 6 months, whichever comes first. Someone on Facebook told me that synthetics don't have the same acid problem that conventionals have, so mileage is the only thing determining when one should change their oil. Definitely interested in this as a few vehicles I have don't even see 3,000 miles in a year, but I have been changing them yearly with Synthetic SuperTech pretty much because I'm afraid of acid buildup. I'd love to replace my synthetic oil every 3 years if it really doesn't cause any harm. Is this claim that synthetics don't form acids based on typically higher TBN values, or is there more to it?