Roof coat or Bed liner?

I have two M146's that need to have the roof sealed, they leak when it rains. Have heard that someone used bed liner on the roof of their M109 (i think). I'm wondering about whether that would be better than doing some kind of mobile home roof coat. I'm guessing that it would cost more, still need to look into that.

Looking at the roof it looks like I need to tryand scrape off as much of the old tar on the seams as I can. Then re-tar and coat the whole thing. I have heard that I then need to re-coat it every year to keep the tar from drying out and cracking.

What are you guys using to seal the roofs on trailers?

I used Pro Flex RV Instant Roof Repair (PDF) on my 109 box roof and painted over it. So far so good. It's supposed to be guaranteed for 10 years.
http://www.geocelusa.com/core/prdb/...p?pdf=prdb_product_tech_data_sheet_pdf_41.pdf

or a good quality silicone chalking.

i used roll on bed liner because the rv roof coatings are all white. i don't know about mobil home coating. the bed liner
worked great.