E5 or E10 fuel any preference and additive addition?

[purple charlie]

probably been asked before but ... the C4 is my 3rd American but last Trans Am was over 20 years ago
5.7tpi should I be using E5 or E10 fuel? previously unleaded or leaded were the options.
further to this, would it need any fuel additive?

my background is in bikes and have been though the ethanol debate before on them.

 

[teamzr1]

GM did NOT even use fuel system parts that would live with Ethanol until around mid 2010
so the older the vehicle is the more apt that Ethanol will degrade parts like inside fuel tank to fuel injectors

Do not use E10 at all and your stuck using E5 and use products to keep fuel system clean
Your lucky only that in the USA they force E10 and E15 on us ( I only use non Ethanol gas in my C5)

The higher the Ethanol percent is,
the leaner the AFR will be and induce more engine knock and misfires with less fuel mileage