Shower Base

[whutfles]

Has anyone had any issues with their shower base breaking? We have a 2010 Montanna Mountaineer 326RLT. We noticed occasional water on the floor outside the shower near the base the first year we bought it new. Never could pinpoint where it was comming from. it has a garden tub with sides about a foot high and the glass door and enclosure on top of that. We thought maybe the water was comming from the seal between the glass and the top of the tub or where the glass meets the wall. We added a little extra caulking. Wasn't much water just a little now and then. Kinda dried up for a few years. Then in 2017 we noticed it again. Found water starting to run down the drain in the garage. Checked the base closer and found about a 10" horizontal separation on the wall side of the tub about an inch above the bottom. Repaired it with rubber roof tape and it has held all of last year and 3 mos this year.

I've purchased a new tub and am getting ready to install it. The old tub and the new tub both have 3/4" styrofoam glued to the bottom. I notice when I stand in the old tub that there is a lot of flexing of the tub when my weight compresses the styrofoam. I can actually feel depressions where I normally stand like the styrofoam is permenently compressed. So I purchased a 3/4" rubber mat from Tractor Supply and am going to cut a piece to the same demensions as the styrofoam. Then I want to remove the styrofoam from the new tub and replace it with the rubber one. Does anyone know of any reason not to do this? I realize it's a little heavier, but that's OK. What type of glue or adhesive should I use to attach the rubber to the new tub? Will PL400 construction glue work? Or should I just use silicone, or something else?

I also purchased a new suround (plastic) for the 2 walls. I was told by the dealer to drill out the plastic push pins or bolts holding it to the wall. Does anyone know what size drill to use? The new suround didn't come with replacement push pins or bolts. Where do you get these?