*I bought an after market air filter , used for less than 10K miles and during that time I had a UOA that showed increased levels of silicon . I checked the slide in after market air filter and it was relatively clean so the high levels of silicon perplexed me . In order to try and remedy the problem I bought a genuine Hyundai Air filter for my 2017 Sonata and installed it : What I first noticed was the snug fit while being installed - no side ways wiggle at all as compared to the after market air filter . Also when comparing the two air filters the Hyundai air filter has wider gasketing material than the after market air filter . What I conclude is that after comparing the the Hyundai OEM air filter against the after market filter is while the filter media appeared similar , both had twist locking tabs - the Hyundai air filter has a wider gasket and a tighter fit with no side ways play at all . I now believe dirt (silicon) levels increased in my UOA with the after market air filter because silicon was skirting around the loose fit of the after market air filter and sneaking into the engine from the sides of the loose fitting after market air filter . Perhaps not all after market air filters are not loose but I do not want to find out . In my case , Hyundai OEM air filters fit best and due to my previous UOA increased levels of silicon with the after market air filter I have permanently switched to Hyundai OEM air filters for my Sonata .