Will I lose my rv if I file chapter 7?

That depends on your requirements for such a large RV. If it is a luxury item for recreation and the monthly payments are high, then it might not be reasonable for you to pay for the RV and not pay your creditors. The Trustee will ask you why you should be allowed to use your money to pay for the RV and have your debts discharged, particularly since you have no equity in the RV to protect. In effect, you would be asking your creditors to pay for your upside down RV. The objection might be on the basis of bad faith. This all depends on the numbers involved, your income, where you are going to file, the value of other assets, and much more you are not disclosing in your question that you need to discuss with a local bankruptcy attorney who you should hire to represent you. As far as keeping your house and car depends on the amount of equity you have and your age, disability status and maybe even your income over the past year. Again, don't even think about filing without competent legal representation by a bankruptcy attorney as there is lot of risk involved and you cannot dismiss a Chapter 7 without Court permission if things go bad.

Insufficient information to say for sure, because this will depend on the exemptions of your particular state and the prevailing attitudes of the Chapter 7 trustees and judges in your federal district.