Welcome to GasSavers!
First off post up Garage entries for your vehicles and a Gas Log if you have the info . It will help you keep track of whats working with your efforts . It will help us learn too .
As far as the motorhome ...park it , pack a tent in the Saturn
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I just improved the FE a bunch
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(or better still rent a cabin or motel room iffn you are into more luxurious surroundings) ...sorry I had to
Much to be learned here , stick around !