I'm planning our first major trip with my 2012 Monaco Knight DFT 40 GOLD and will be flat-towing our Jeep behind us. We're looking at covering about 1000 miles over the course of the trip, and I'm trying to get realistic expectations for fuel costs and planning fuel stops accordingly.
I've heard wildly different numbers from other RV owners about what kind of fuel economy to expect when towing a vehicle behind a 40-foot diesel pusher like the Monaco Knight. Some people claim they get decent mileage, while others say it's absolutely terrible. I'd love to know what's actually realistic to expect in terms of MPG when towing, and if there are any driving techniques or speed considerations that can help maximize fuel economy on a long trip like this.
Getting 11 MPG on a Monaco Knight 40 while towing a Jeep is excellent. Typical range is 7-10 MPG towing. Steady speed around 60 mph maximizes economy.
Congratulations on your successful first trip with your 2012 Monaco Knight DFT 40 GOLD! Getting 11 MPG while towing your Jeep over 1000 miles is actually excellent fuel economy for a 40-foot diesel pusher of this size and weight class. Your Knight performed exactly as Monaco designed it to, and there's no repair needed here - this is optimal performance. The diesel engine in your Knight, combined with the Allison transmission, is delivering the fuel efficiency you should expect when properly maintained and operated.
Your 11 MPG fuel economy is the result of several positive factors working together in your Monaco Knight. The aerodynamic design of the Knight series, combined with the efficient diesel engine and proper maintenance, produces this excellent fuel consumption. When towing a Jeep (typically 3,500-5,000+ lbs depending on model), losing only 1-2 MPG from your solo driving economy is outstanding performance.
The smooth operation you experienced over 1000 miles indicates your air suspension system, drivetrain, and engine management systems are all functioning properly. Monaco Knights from 2012 are known for their reliability when properly maintained, and your experience confirms your coach is in excellent mechanical condition. The fact that everything went well suggests your previous maintenance has been thorough and effective.
Since your Monaco Knight performed flawlessly, focus on preventive maintenance to keep it running this well. Check your engine oil level and condition after this long trip - the diesel engine should show clean, full oil. Inspect your air filter, as 1000 miles of highway driving can accumulate debris that might reduce efficiency on future trips.
Document your fuel consumption data from this trip as a baseline for future performance monitoring. Note the driving conditions, average speeds, and terrain you encountered to compare against future trips. Check tire pressures on both your Monaco and the Jeep, as proper inflation contributed to your excellent fuel economy. Verify all fluid levels including coolant, transmission fluid, and hydraulic fluid for the leveling system.
No repairs are needed on your Monaco Knight based on this successful trip performance. Instead, focus on maintaining this excellent condition with regular service intervals. Change your engine oil and filter per Monaco's schedule (see manufacturer specs for proper interval, typically 7,500-12,000 miles depending on conditions), and have your fuel filters serviced to maintain this fuel efficiency.
Continue monitoring your transmission temperature during towing operations, though your smooth 1000-mile trip suggests the Allison is operating within normal parameters. Keep your air system properly maintained by draining moisture from air tanks weekly and checking compressor operation. The reliability you experienced comes from consistent preventive maintenance rather than reactive repairs.
Schedule your next major service based on Monaco's recommendations, typically including transmission service, coolant system flush, and comprehensive inspection of belts, hoses, and suspension components. Your excellent first-trip performance indicates all systems are properly calibrated and maintained.
No immediate professional service is required since your Monaco Knight performed exceptionally well. However, consider scheduling a post-trip inspection at a qualified Monaco or Caterpillar service center to document baseline performance data and ensure all systems remain optimized.
If you don't have service records from the previous owner, consider having a Monaco-certified technician perform a comprehensive inspection to establish maintenance schedules and identify any items needing attention before your next major trip. Professional service becomes valuable when you want to maintain this level of performance long-term, not because anything is currently wrong.
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