Loud humming noise coming from the right front tire.
Hello there, many different faults will cause a humming noise from the front tire of your 2008 Kia Optima. The most common would be a failing tire, wheel balance, wheel bearing (https://www.yourmechanic.com/services/wheel-bearings-replacement), dragging brake pad (https://www.yourmechanic.com/services/brake-pads-replacement), sticking caliper (https://www.yourmechanic.com/services/brake-caliper-replacement), or...