I tow with an Expedition. With the turn signal under the mirror, I had problems finding anything that would stay on, especially on the passenger side. I have lost 2 or 3 mirrors on the side of the road, and the cheap ones I had bought vibrated terribly (all 3 different styles). I just got a set of Grand Aero mirrors and I LOVE them. No vibrations, and they clamp to the top of my mirrors, so I can still use the regular mirror as a blind spot mirror. I wish I would have gotten them first and not wasted my money on the cheap ones.