Originally Posted by Brother Les
IF you have an access panel where you can look under your tub, you should do so. I also had a 'give' in my tub near the drain. I looked under the tub one day and found that the 'support' board was supporting nothing and hanging in mid air. I braced up the support board with 2x4 screwed into it and to the floor. No more give. There was no way in the world that the RV builder could have missed the support board 'hanging' in mid air. They were too lazy to take the time to fix it right.
I'll have to take a look. Thanks for the "heads up".