There are a few issues that you will need to check out on your RV prior to using it with carseats:
* Most RVs have the rear seats bolted to plywood flooring, not to the actual steel frame of the vehicle. They may not hold well during a car crash.
* All carseats must be installed in a forward facing seat. Often, you will find sideways facing seats or rearfacing seats in RVs which will not work with carseats.
* For a booster (not using a harness), a lap and shoulder belt will be required which would force the boostered child into the front passenger seat. This may leave another adult in a not-so-safe seating position in a lap-only seat in the back. Lap belts aren't a good idea for either kids or adults due to the risk of internal injuries.
* For seats such as at a dinette area, there often isn't sufficient clearance between the table and the seat to protect a child or adult who may be sitting there. If someone is sitting in a dinette seat, make sure the table is removed first so that they don't hit the table during a crash.
Often when dealing with RVs, especially if renting one, it is best to get a pull-behind one or a 5th wheel one as then you can utilize your truck for transporting everyone safely and still have the luxury of your RV when you get to your destination.