Eric in Santee

I have the classic AFM related spark plug fouling issue on my 2010 Silverado 5.3 liter V-8. I already replaced the valve covers with the new ones recommended by GM. I replaced the plugs along with the valve covers 20k miles ago but now the truck is running rough again and the check engine light cam on just like last time. I assume the plugs are fouled again but I haven't pulled them yet. I have read that if I drive the vehicle in manual mode in 5th gear it will de-active the AFM. Is this an acceptable long-term solution? I like the truck but having to replace spark plugs every 20K miles is a total pain in the butt. Thanks.