Diesel Fuel Mileage Est.

naturist wrote:
Those folks who claim diesel isn’t economically warranted have never had a diesel, I suspect. I’ve now had three diesel vehicles, a car and two SUVs. All three got about 1/3 farther on a gallon of fuel than gas engines versions of the same vehicle. Towing our TT, 5,000 lbs gross weight, we average 14, but have gotten 17 a couple times and once got only 9 (into a 50 mph headwind).

Had a diesel but the last 2 trucks have been gas. Went from 9k to 12k 5ers in that time.

There are two major considerations:
- New vs Used
- How many miles do you tow per year.

With New, it's very hard to make up the initial $8-10k upcharge for diesel along with higher maintenance costs over the life. With used, as the age gets older, the upcharge gets depreciated. By 10-15yrs, there isn't a great deal of price difference for equivalent trucks. The biggest issue is finding a low mileage diesel in good condition at that age.

For a typical RV'er towing 2-5k miles per year, no way you will ever cover the cost on a new truck. But if you are running the carney circuit doing 50k miles per year of towing, it can be done.

For most mortals, the real reason to get diesel is you are pulling a really big load and/or doing a lot of mountain towing.
- The highest tow ratings are with diesels.
- In mountains, the turbo on the diesel means you won't lose 20-40% of power as you gain altitude. Also the new trucks have built in exhaust breaks that really help going down long grades.

I get 10-12 towing my 9500lb 35ft TT towing at 60-65. I get 12-14 towing my 7x14ft 5Klb cargo trailer at the same speeds on the same roads. Once a trailer is hooked up, unless it's a pop up, mileage is in the tank. Now on my 2015 duramax I average 18-20 on the highway going speed limit to 5 over. My 2004 duramax got about the same mileage towing, but 16-18 on the same highway trips. And the 5 over includes idaho and Mt with 75 and 80mph limits. Going to southern CA we get 20 mpg consistently. Hand calculated, the DIC is optimistic.

Previously with 2014 Chevy 2500 HD 6.0 I got 6-8 towing (best towing mpg was 8.1) 13-14 highway not towing
Currently with 2017 Ram 3500 6.7 I get 10-12 towing 20-22 highway not towing (best was 25 mpg on flat terrain)

Maintenance costs have not been significant enough to keep track of. 2 oil changes a year and fuel filters every 15,000 miles.

2017 Duramax here pulling a 6000 lb. 24 foot trailer. From Michigan to Oregon mostly all up hill 12.5 mpg. From Oregon / California border home mostly all down hill 13.5. MPG There we some side trips without the the trailer but you get the gist. The trip turned out to be 7400 Miles. My truck has the 36 gallon tank and could easily do 400 miles or one day of driving.

naturist wrote:
Those folks who claim diesel isn’t economically warranted have never had a diesel, I suspect. I’ve now had three diesel vehicles, a car and two SUVs. All three got about 1/3 farther on a gallon of fuel than gas engines versions of the same vehicle. Towing our TT, 5,000 lbs gross weight, we average 14, but have gotten 17 a couple times and once got only 9 (into a 50 mph headwind).

I have had several. I have a 40 DP now. A DP isn’t even in the discussion as you can’t have a 30-40K pound gas coach.

Pay $4-10k more plus fuel is 40-50 cent/gal higher, higher maintenance $,
You would have to drive 300-400k miles to break even and nobody keeps them that long.

If you want the power to go up the hill a little faster more power to you (yuk).

There are diesel vs gas calculators out there if you want to look.

And lord help you if you bought a 6.2 GM or a 6.0 Ford.

12-14 real world mpg towing.

Money isn't everything, buy a diesel ;)

I paid for my diesel with fuel savings. More importantly, I got the massive improvement in towing performance.
The best part is you will get the value of the diesel back or even more, when you sell. So paying for it with improved mileage isn't important.

After you've had one, the cost will be unimportant either way. You'll just enjoy the experience.

Those folks who claim diesel isn’t economically warranted have never had a diesel, I suspect. I’ve now had three diesel vehicles, a car and two SUVs. All three got about 1/3 farther on a gallon of fuel than gas engines versions of the same vehicle. Towing our TT, 5,000 lbs gross weight, we average 14, but have gotten 17 a couple times and once got only 9 (into a 50 mph headwind).

Jayco23FB wrote:
Hello,
I am considering moving to a deisel engine in my next truck. Primary reason is for increased fuel mileage. I tow a 23' travel trailer that weighs approx 6,000 lbs loaded. I know there are many variables such as make etc. I am just wondering if anyone out there has a simular unit using a 3/4 ton truck, automatic with a deisel engine that could provide a real world estimate of fuel mileage. Thank you.

I love my diesel, but it would be overkill for what you need. Btw I get 12-13 pulling 10k

Dan

With my 1999 Dodge 2500 Cummins 24 valve diesel 4x4 with 410 gears and OD, we got 16.1 mpg towing our tri axle Stealth Toy Hauler, around 12000lbs on our last trip. Now this is in California at 55mph. Not towing, the best I have recorded was 25.7 mpg. I do read on these Forums that it cost more to maintain a diesel. That is not true. Oil and filters every 5000-7000 miles. No plugs, plug wires, etc. Actually it costs more for a gas engine.