Longtime Nissan owner/driver. My dad has a Titan and I got him the Billet Grille for Christmas off of eBay. (can't post link to item since I'm under 15 posts)
He's installed the grille and has had some issues with a whistling sound. Tried with and without the plastic pieces behind the grille to no avail (I assume they are involved in some sort of airflow re-direct or something?). I'm far from a gearhead, but much more familiar with my car than these big ol' trucks. Is this a common problem and is there a known fix for this?
(picture of grille attached)