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slowmover · 11-23-2014, 07:08 AM

after completing a 5000 mile road trip in my 2001 Dodge Ram 3500 4x4 Diesel truck hauling a 27' 5th wheel trailer. I managed a trip average of just over 12.9mpg. My best tank was 13.2mpg.

Some years back I researched the later HPCR Cummins TurboDiesels and how well they were pulling aero all-aluminum travel trailers as that combo is also mine. I found over one dozen reports where the TT in question was from 28-35' in length and weight from 7-11k pounds. Mainly in South Central US. 14-16 mpg was the range where travel speed was 58-62 mph, overall (some claimed more and at a higher travel speed. I wasn't always able to get confirmation about written reports or how well records were kept).

I found 15+ was easy at 62-63 mph. So 16-mpg at my now-usual 58-mph is easy. Goal is to be 17 as an average in the future (for warm climate, low altitude cruising on non-hilly Interstate). And that goal will be from quite careful trip planning and execution. I wish to know my top possible number.

The difference from 13 to 16 is an improvement of about 18% (for averages). That, I'm guessing based on some experience and reading around, is the likely top for a 1T diesel truck pulling most any kind of trailer.

Hitting the 20's will be with a TD car or SUV. Maybe up to 22' with a post 1990 Airstream (to keep restoration costs low). An OLIVER or CASITA would be just as high, maybe higher, so look at them as well. We've one contributor here with a 5'er SCAMP who does 15-mpg with a small gasser pickup (KamperBob).

So, while a trailed combination is likely to be higher (and with a tow vehicle that for solo miles is also quite fuel efficient which is the majority of miles), a moho has to answer the question that really kills average mpg. And that is how long can one park without re-supply be it food, water or propane?

Yes, one can design a scenario where a giant moho can burn less fuel overall than many or most other combinations where extended off-grid parking is expected due to huge onboard capacities. So how one travels is key. But the usual scenario is to move every few days for re-supply or to tow another vehicle. Neither is in any way fuel efficient.

Outline how one expects to travel and this thread will gain some traction. A single man moving every few days is one thing, a family of seven staying three weeks at a time in one spot is another. And so forth.

Staying in motels isn't the cheapest. Cheapest is sleeping on the Grey Dog en-route. An RV has to be put into context.

.

11-23-2014, 07:08 AM	#14 (permalink)
slowmover Banned Join Date: Oct 2009 Location: Fort Worth, Texas Posts: 2,442 2004 CTD - '04 DODGE RAM 2500 SLT Team Cummins 90 day: 19.36 mpg (US) Thanks: 1,422 Thanked 737 Times in 557 Posts	after completing a 5000 mile road trip in my 2001 Dodge Ram 3500 4x4 Diesel truck hauling a 27' 5th wheel trailer. I managed a trip average of just over 12.9mpg. My best tank was 13.2mpg. Some years back I researched the later HPCR Cummins TurboDiesels and how well they were pulling aero all-aluminum travel trailers as that combo is also mine. I found over one dozen reports where the TT in question was from 28-35' in length and weight from 7-11k pounds. Mainly in South Central US. 14-16 mpg was the range where travel speed was 58-62 mph, overall (some claimed more and at a higher travel speed. I wasn't always able to get confirmation about written reports or how well records were kept). I found 15+ was easy at 62-63 mph. So 16-mpg at my now-usual 58-mph is easy. Goal is to be 17 as an average in the future (for warm climate, low altitude cruising on non-hilly Interstate). And that goal will be from quite careful trip planning and execution. I wish to know my top possible number. The difference from 13 to 16 is an improvement of about 18% (for averages). That, I'm guessing based on some experience and reading around, is the likely top for a 1T diesel truck pulling most any kind of trailer. Hitting the 20's will be with a TD car or SUV. Maybe up to 22' with a post 1990 Airstream (to keep restoration costs low). An OLIVER or CASITA would be just as high, maybe higher, so look at them as well. We've one contributor here with a 5'er SCAMP who does 15-mpg with a small gasser pickup (KamperBob). So, while a trailed combination is likely to be higher (and with a tow vehicle that for solo miles is also quite fuel efficient which is the majority of miles), a moho has to answer the question that really kills average mpg. And that is how long can one park without re-supply be it food, water or propane? Yes, one can design a scenario where a giant moho can burn less fuel overall than many or most other combinations where extended off-grid parking is expected due to huge onboard capacities. So how one travels is key. But the usual scenario is to move every few days for re-supply or to tow another vehicle. Neither is in any way fuel efficient. Outline how one expects to travel and this thread will gain some traction. A single man moving every few days is one thing, a family of seven staying three weeks at a time in one spot is another. And so forth. Staying in motels isn't the cheapest. Cheapest is sleeping on the Grey Dog en-route. An RV has to be put into context. .