I bet it was too loud! Towing always brings the “air hammer chiseling frame bolts under a truck” sound out of an already noisy exhaust systemHow my 97 was for a while. I had the 3" GM dual tubing, high flow cats into a Y-into a 3.5" tailpipe. When I put the Thorleys on it and started towing my travel trailer it was just too loud. For short trips, not towing I miss the sound. I had electric cutouts on it but one of the motors went bad.
Our shop truck is a 460 powered ford with true duals and super 10s. Makes my eyes water when we hook up a trailer to it.