I have a water leak causing low pressure and continuous pump running, it leaks underneath about in line with the sink in the galley, I searched everywhere i could, I even opened the wood panel under the sink floor, I can see where the water comes from when I crawl under the coach, but ther,s a steel panelling hiding everything. any suggestions or same experience?

Thanks very much for your help

Just logged on for the first time and saw your problem.  know what?  I think I have something similar.  Last year when I was flushing the tanks for storing for the year, I ran the water in the bathroom sink and saw water dripping out from underneath.  I didn't do anything about it then as was putting into storage.  Now I am getting ready to take some trips and have to have some other work done on it.  I had a friend crawl under the rig to see if he could see a crack but saw same as you.  fully enclosed bottom.  I am wondering if you got any answer to this problem? 

The other problem I have with my 2008 Tioga is that for the first time last year I extended the slideout and found that the whole seal is gone on it.  I have a cat so could not use this at all.  Not happy about that esp since I have not had the opportunity to use this motor home that much.  I await your reply........Pat