1. Aerodynamics:
* Reduce drag: This is the biggest potential gain. Anything protruding from the RV increases drag significantly. Consider removing unnecessary items from the roof rack. If possible, a fairing (a streamlined cover) for the front of the RV could help, though this is a significant modification.
* Lower the profile: Removing heavy items from the RV reduces weight, which can slightly improve gas mileage. Every pound counts.
2. Weight Reduction:
* Remove unnecessary items: This is crucial. The heavier the RV, the harder the engine works. Go through everything and remove anything not essential for your trips.
* Lightweighting: Replacing heavy components with lighter alternatives (where feasible and safe) can help. This might involve things like aluminum wheels or replacing heavy furniture. This is often expensive and requires significant work.
3. Engine and Drivetrain Maintenance:
* Regular maintenance: This is fundamental. Ensure your engine is properly tuned, including spark plugs, air filter, fuel filter, and distributor cap (if applicable). A poorly maintained engine will significantly reduce MPG.
* Proper tire inflation: Under-inflated tires increase rolling resistance and reduce fuel economy. Check your tire pressure regularly and inflate them to the recommended PSI (found on the tire sidewall or the driver's side doorjamb).
* Transmission fluid: Ensure the transmission fluid is clean and at the correct level. A slipping transmission consumes more fuel.
* Differential fluid: Check and change the differential fluid as recommended. Proper lubrication is crucial for efficient drivetrain performance.
* Alignment: Proper wheel alignment reduces tire wear and improves fuel economy.
4. Driving Habits:
* Drive smoothly: Avoid aggressive acceleration and braking. Smooth, consistent driving conserves fuel.
* Maintain a consistent speed: Avoid excessive speeding. Fuel efficiency is often best at moderate speeds (around 50-55 mph, depending on the vehicle). Wind resistance greatly increases at higher speeds.
* Plan your routes: Avoid unnecessary stops and idling. Use GPS to find the most efficient route and avoid hilly terrain if possible.
5. Consider (but carefully evaluate cost/benefit):
* Overdrive transmission: If your RV doesn't have one already, it's unlikely to be cost-effective to add one to an older vehicle.
* Fuel additives: These are generally minimally effective, but some swear by them. Research and be skeptical.
* Engine upgrades: This is usually not practical or cost-effective for an older RV.
Important Note: The gas mileage improvement from these changes might be modest, perhaps 1-3 mpg at best. A 1992 Class C RV will never be fuel-efficient by modern standards. The focus should be on maximizing the existing system's efficiency rather than expecting dramatic changes. Manage expectations realistically.
