Some truckers are going to a single antenna on the center back of the cab. I was told that singles work better. I used to run dual antennas on my pickup using the front bed stake holes. Worked ok, but if not tuned right, I think they actually almost cancel each other out. I now use a single Lil Wil magnet mount and it works ok even with my camper hooked up. It has more with to do with it being tuned (right length for the radio wave). Check with a CB shop if your CB isn't working well. It may be an easy fix with the current setup.