boxofdelights

I think, possibly, that companies are overcautious about the recommendation of a particular octane of fuel because people could misunderstand and/or that if they say that 85 is okay at a mile high people might blame them for unrelated problems and sue. Some mechanics go with the recommendation of the company without necessarily thinking much about it. Bottom line if you start hearing knocking type noises you do need 87, but otherwise you are 99% likely to be fine.