New to all this..

Lynnmor wrote:
Make your best guess as to where the studs are using a stud finder. Drill a tiny hole and insert a bent paper clip and probe side to side to see if you are in a stud or if there is one nearby. If it is a no go, fill the tiny hole and try again.

They use steel plate backers, try using a magnet and looking for the plate in the area you would mount a TV. They are not always where you would think, I had one at 90 angle to the couch. I have found inspection scopes to be a handy tool for "looking inside."

Scope

If you have a wood framed trailer, the wall panels aren't that difficult to remove. Find the seams, and you can probably get a flat 90* pry bar underneath the panel and pop the staples loose. Same thing should go for interior walls on a lightweight trailer. With the wall open, you have other options and could put in a cripple stud or a plywood sheet to help carry the weight of the TV mount.

If it's aluminum framed, 99% chance the wall panels are laminated around the actual frame so don't even think of removing... An infrared camera might help show where the studs are because there won't be any styrofoam insulation on the studs.

Lynnmor wrote:
Water lines in exterior walls??? What keeps them from freezing? Not many electrical lines in exterior walls, if there are any there should be an outlet of some sort in the area.

Nothing keeps them from freezing, that's why you have to winterize a trailer, as far as electrical, they run it wherever they please, watch a video on how RVs are made, there's no code like in residential housing so they run them in flooring, ceiling, and outside walls.

Thank you guys for all of your help. I'm a welder by trade so I'm going to make add onto the existing mount and make it a bit longer. It says it can hold up to 25 pounds and the tv is 8.9 so i should be ok.

Just press in along the wall. You will find where it bows in the most and the least/not at all. Do not use screws longer than 1&1/2” except to allow for any mounting board depth.
Most mount a board across at least two studs to allow more positioning options.
I mounted an articulated arm mount for a 21” LED lightweight television. So I used two short lag screws into an exterior wall stud.
That was my second location. First location, with same arm, was on the end of the kitchen cabinet. I reinforced the panel & frame inside but people kept hitting their heads on theTV ;(

Water lines in exterior walls??? What keeps them from freezing? Not many electrical lines in exterior walls, if there are any there should be an outlet of some sort in the area.

Follow Bob's advice. Use the plywood and you'll be fine.

Lynnmor
While what you say is correct, they know where the studs or plates are, he does not. I would rather not read another post where someone has drilled into a water or electrical line or worse the outside wall of their unit.

bgum wrote:
Do not consider mounting anything to the 4 outside walls, ceiling, floor, or any wall shared with the shower. You may be able to use a square of plywood as a backing to one of the flimsy inside walls.

Many TV mounts are on the outside walls. Some trailer manufacturers use sheet metal just behind the paneling and that can be found using a strong magnet. Sheet metal screws are used for mounting in this case.

Make your best guess as to where the studs are using a stud finder. Drill a tiny hole and insert a bent paper clip and probe side to side to see if you are in a stud or if there is one nearby. If it is a no go, fill the tiny hole and try again.