Diesel Fuel Mileage Est.

[Jayco23FB]

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.

[HuckleberryHunt]

Grit dog wrote:

HuckleberryHunter wrote:
Similar trailer specs to yours. My 2003 1/2 ton Silverado v8 gasser got 10-12 mpg towing. My 2016 3/4 ton Silverado diesel gets 10-12 mpg towing. Fortunately in my area diesel tends to be cheaper than gas, but it’s marginal. FYI.
The only way to get much better mileage is to get a pre-emission year diesel or do a delete on a newer one.

There is about 0 chance of this in an apples to apples comparison.

Then you missed the point. I was not comparing the towing capabilities of the two dramatically different tow vehicles. I was comparing relative gas milage between two different vehicles towing the same TT. The point being that for those who think moving to a diesel may provide dramatically improved gas milage might be disappointed. This is one example and those others posted are additional info. But, thanks for your opinion and the additional info.

[Grit_dog]

Bottom line, don't buy a diesel for the fuel mileage, although it's a nice little perk.
Buy one because you want one, need one, or so you can get you b@lls back out of your wife's purse!

On a more serious note, yes the $8k upcharge new is significant, and not for the weak wallets, but those that claim "increased cost of ___, and loud smelly, never get your money back...etc" are typically gas HD pickup drivers who won't admit they wished they had double the torque and could actually get double digit mileage numbers doing anything but running empty down the highway!
BTW, the naysayers can show me where any diesels, save for the old turds and the 6.0 Fords and to a small extent the 6.4s, don't recover most or all of the upcharge on resale compared to an equivalent gasser. You won't be able to. You'll get your money back when you sell it.

[Grit_dog]

Cummins12V98 wrote:
"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"

Must have had a nice tail wind!

Yeah, lol! Sounds like a couple of my buddies who drive like @ss hats, but somehow get 20-25mpg empty and 15 towing!

[Grit_dog]

HuckleberryHunter wrote:
Similar trailer specs to yours. My 2003 1/2 ton Silverado v8 gasser got 10-12 mpg towing. My 2016 3/4 ton Silverado diesel gets 10-12 mpg towing. Fortunately in my area diesel tends to be cheaper than gas, but it’s marginal. FYI.
The only way to get much better mileage is to get a pre-emission year diesel or do a delete on a newer one.

There is about 0 chance of this in an apples to apples comparison.
Also the delete statement with respect to significant mileage difference only holds true for dpf equipped trucks, pre def/scr. I.E. 07-10 models of all 3 and up to 13-14model Rams.

[HuckleberryHunt]

This whole thread has made me feel a bit better about our diesel purchase. Prior to purchasing our 2016 Duramax, I was told by many that the pre-DEF models were the way to go and wondered if I should have gone that route....not that DEF is fun to deal with, but at least it doesn't appear to have had a severe impact on overall milage as my numbers reflect what many have already posted. I do often wonder what it would be if you could pull the emissions portion out as I too see the milage drop dramatically when it goes into re-gen, but I'm not the type to get into that type of thing. I do love how it pulls the TT with ease up and over the Passes. I'll just continue to enjoy the experience.

[wnjj]

Cummins12V98 wrote:

fj12ryder wrote:

Cummins12V98 wrote:
"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"

Must have had a nice tail wind!

We were coming downhill from Albuquerque to Amarillo with an almost 40 mph tailwind the whole way and averaged 14 mpg. That's with a 2001 Dodge Cummins dually pulling a 15,000 lb. triple axle toyhauler. When we pulled our Big Sky at 12,000 lbs. we would average around 12 mpg. These are real world figures, not off the overhead monitor.

16.1 must have been on a downhill 2 mile stretch with a tailwind and the motor idling in neutral, and figuring mileage off the overhead monitor. That's about the only way.

Yup! I towed many thousands of miles with a 98 12V 2500 4x4. My combined weight was 20,500#. It had Bosch 215 injectors with alternate timing. It got great mileage. It NEVER made 16mpg even with a good tailwind!!!

Or the odometer is cranking on the miles a bit too fast.

[Cummins12V98]

fj12ryder wrote:

Cummins12V98 wrote:
"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"

Must have had a nice tail wind!

We were coming downhill from Albuquerque to Amarillo with an almost 40 mph tailwind the whole way and averaged 14 mpg. That's with a 2001 Dodge Cummins dually pulling a 15,000 lb. triple axle toyhauler. When we pulled our Big Sky at 12,000 lbs. we would average around 12 mpg. These are real world figures, not off the overhead monitor.

16.1 must have been on a downhill 2 mile stretch with a tailwind and the motor idling in neutral, and figuring mileage off the overhead monitor. That's about the only way.

Yup! I towed many thousands of miles with a 98 12V 2500 4x4. My combined weight was 20,500#. It had Bosch 215 injectors with alternate timing. It got great mileage. It NEVER made 16mpg even with a good tailwind!!!

[fj12ryder]

Cummins12V98 wrote:
"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"

Must have had a nice tail wind!

We were coming downhill from Albuquerque to Amarillo with an almost 40 mph tailwind the whole way and averaged 14 mpg. That's with a 2001 Dodge Cummins dually pulling a 15,000 lb. triple axle toyhauler. When we pulled our Big Sky at 12,000 lbs. we would average around 12 mpg. These are real world figures, not off the overhead monitor.

16.1 must have been on a downhill 2 mile stretch with a tailwind and the motor idling in neutral, and figuring mileage off the overhead monitor. That's about the only way.

[DustyR]

Towing with the vehicle in my sig, on a trip from Harlingen, TX to Fairmont, WV. I averaged on the leg to Nashville, TN 12.8 MPG. The overall mileage to WV was 12.3 mpg.
The trailer scaled out at 8700 pounds and tow speed was 55 - 65 mph. The major difference between towing with a gasser is the ease that the diesels torque gets the load down the highway.

My Tundra pulling the same trip earlier averaged 7.5 Mph, quite a difference in mileage. The original difference in vehicle purchase price would help to offset the difference in mileage if the gasser was set up to handle the weight.

The Tundra on a good day empty would average 13+ MPH empty and the Diesel on a bad day 13.5 empty. The long and short of it is comparing apples to oranges. One is designed to haul a load and the other is a compromise. Compromise is good for the short haul and easier on the wallet.

[4x4ord]

I really appreciate the way the diesel engines pull and would have a hard time giving mine up but if the most I was planning on towing was 6000 lbs I might try a 1/2 ton. I get about 9 mpg towing.

[Cummins12V98]

"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"

Must have had a nice tail wind!

[valhalla360]

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.

[ktmrfs]

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.

[Chase_WV]

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.

[JCK]

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.