The bottom line is pretty simple....

Use what the manufacturer recommends. They are telling you what the engine was designed to run on. Using anything else will likely have a negative effect on both your performance and fuel economy.

(I'm sure someone somewhere will post that in THEIR car THEY got better performance using a different fuel rating than recommended. In reality, your car will run best on what is recommended unless there is a problem with your vehicle...in which case the right action is to get it fixed not change fuel rating.)

-Tim

2006 Mercury Mariner Hybrid AWD
Black with Pebble interior
Premium Package with Nav & Moonroof



Current ODO: 22,909
Typical Drive: 20 min crosstown in heavy traffic (3.5mi there and back twice a day)


457 Gallons of gas saved
That's 9,150 lbs less CO2