The only RV park in Mexico City is:
Pepe'RV Park
San Martin 54600
Av. Eva Samano de Lopes Mateos 62
Tepotzotltan Estado de Mexico
Mexico
Tel +52 55 1259 5129
It is the only RV park in the valley of Mexico City after passing the toll both the entrace to the town of Tepotzotlan is pretty close and immediately to the right, I recomend that you look on google maps the layout of the town , you need to go arround the convent and the street where it is located is easy to miss.
Do not confuse the town of Tepotzotlan with the town better known to the tourists as Tepostlan, that is in the state of Morelos between Cuernavaca and Cuahutla.
Regarding the repairs that you need, it is better if they are done State side, RV's are rare in Mexico.
navegator