Some, especially high-performance vehicles, recommend 89 (midgrade or plus) or 91+ (premium). Unless the vehicle manufacturer recommends or requires the use of premium fuel, there is no advantage to using a higher grade (octane rating) gas. All vehicles use a fuel filter, both in the fuel tank and in the fuel line before the fuel is sent to he fuel injectors, so any dirt or debris is caught before it can enter the engine. Therefore, I recommend using regular grade of fuel in your Chevrolet trucks. Your wallet will like the savings.
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