The question I have is this a change from previous experience? Or has it always done this? I had the same thing happen to my Sabre trailer, albeit its not a tandem. It turned out to be that I needed to bleed the brakes. Once I did, back to “normal”. Id describe mine as a “thud”. The neat thing about my trailer is that there is only one fitting to bleed, the way BCB set up the brake lines is that one line from the actuator goes to the RH wheel, then from there a line runs along the axle to the LH wheel. It takes two folks, one at the actuator with a screw driver to depress the actuator and one at the fitting to open/shut it. As we bled the brakes, it was obvious we were making progress as the actuator became increasing harder to depress. Point being, if you decide to give it a try, you should know right away if youre “on to the problem”.
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