High mileage oils are designed to treat symptoms of higher mileage: leaks/seepage, sludge buildup, ticking noises, etc. (HM oils are typically thicker than their normal oil counterparts.)
Here's the problem: many high mileage vehicles don't show any symptoms yet people still think they should use HM oil.
Don't fix a problem that you don't have. Keep using whatever the manufacturer recommends until you have a reason to change. My Tacoma has nearly 170,000 miles on non-HM oil, and it doesn't leak or tick or show any signs of high mileage. I will switch to HM oil when the symptoms appear, but not before then.
Here's the problem: many high mileage vehicles don't show any symptoms yet people still think they should use HM oil.
Don't fix a problem that you don't have. Keep using whatever the manufacturer recommends until you have a reason to change. My Tacoma has nearly 170,000 miles on non-HM oil, and it doesn't leak or tick or show any signs of high mileage. I will switch to HM oil when the symptoms appear, but not before then.