Water Leakage under subfloor above vapor barrier

[frankguar]

I can use some help. I purchased My 2018 Pioneer RG26 toy hauler August 2022. I have taken it on a few trips and am happy with it.

I load a Harley Davidson ultra limited motorcycle in it and it’s weight is about 850lbs. The floor by the ramp became soft after only a few trips.

Being handy and a retired tradesman decided to repair it myself. On 12/18/23 I rolled back the flooring. I found the ¾” particle board and under side of flooring to have black mold.

There was no visible dampness on the flooring or particle board. I cut the bad ¾ particle board out and found wet insulation and standing water on top of the vapor barrier. I tried using a garden hose to run water from all directions and could not find where the water is coming from. I last used the trailer 10/21/23.

It has been sitting in my driveway since. I have the tongue jack raised high. So the trailer is angled towards the rear. I haven’t had any water leaks, but I did over fill the freshwater tank before my last trip.

Anyone have any ideas where this leak could be coming from?

Any guidance would be appreciated.

 

[Dahillbilly]

could be from any place, I've had two windows that leaked one down the wall & one inside the wall onto top of floor in garage. It's a tough job finding those leaks , took me lots of tsting with garden hose before I found mine. good luck

 

[sengli]

There are alot of places on that ramp door seal area that are prone to leaks. Heck a lot people on here that have the toy haulers, have had the door itself actually get rotted out due to water ingress.

 

[jnbhobe]

Could be from driving in the rain and coming in unsealed wheel wells.

 

[ShannonQ]

We don’t have a toy hauler BUT we do have the black mold, soft floor. It was only at the bottom, not the walls, windows etc. This was on a slide. We found out the water runs down the wall and instead of dripping down on the ground it wicks into the wood/flooring. Obviously a design flaw, maybe something like that is going on?