The maintenance schedule calls for fuel additive every 6000 miles. Exactly what is added to the fuel? Is it an off the shelf product? Why must it be done by a dealer?
I should have provided more context.. I had a 2012 Optima SX 2.0T and learned this from the advisor. I had that car for just a bit under 7 years (bought it new off the lot in 2011). Never had any problems with the engine when I put techron in and it ran great until the day I traded it in. I'll do the same with the GT2