Minor issue. The headrest on my passenger-side seat always slides back down to the lowest position while I'm driving.

Does anyone know if there's a way to tighten this so that it stays in the chosen position?

 

When i had these seats way back, i put a foam block inside the little accordian piece between the headrest/seat. It helped some, but not much of a solution. All that keeps the HR from coming out is a flat spring that locks into a hole on the slider. That spring also puts tension on the slider, but i dont remember a way to put more tension on it.

 

^^^

Thanks. It's a minor issue that I'll likely just have to live with. I'll try something similar to what you did with the foam.