Diesel Towing MPG With Ultralight Trailer

[Grodyman]

Anybody have any idea what a late model 2500 series DIESEL truck pulling a mini trailer 3500lbs max trailer weight would be?

My 2017 3.5 Ecoboost gets about 20 mpg highway empty. It gets 7-9 mpg towing an untralight 4500lb trailer (Passport 153ML), which is terrible (23 gallon fuel tank).

Trying to decide what the best retirement truck is, where I will no longer have a long commute with a lot of empty miles like I do now.

Gman

[carringb]

It's all about wind load and frontal area.

Some of the ultralight teardrop style trailers are terrible of MPGs because the front wall is so far back from the truck. Behind frontal area, trailer gap is the largest contributor to wind drag. Trailer shape is last.

A diesel might be slightly more efficient when towing, but you might find better gains moving to a different trailer. Or just slow down.

[Grodyman]

Lwiddis wrote:
Your F150 should do much better. I get 12 to 13 pulling 5000 pounds but am rarely over 55 mph.

I generally tow 65-70 mph. 7-9 mpg is pretty accurate, maybe as high as 10 max.
Gman

[Grit_dog]

ageilaus, you’re correct, but diesel haterz will always fail to acknowledge the whole story. Idk why, but they do.

[Grit_dog]

mtofell1 wrote:

Grodyman wrote:
It gets 7-9 mpg towing an untralight 4500lb trailer

I'm sensing a litte, "cooking the books" here. I get 9 with a less efficient gas engine pulling an 11,000# 5th wheel out west in the hills. Your Ecoboost has to do better than 7-9 with a 4500# trailer.

It sounds like the diesel will make more sense for range between fuel stops but the money saved on fuel alone will never pencil out in any reasonable amount of time.

Likely the difference in speed and driving habits.
If you get 9mpg with a gasser pulling a 11k 5ver, you are the figurative turtle on the road.
However if a guy is clipping across the country at 75 mph in a eco with a full size TT 7mpg is not at all out of line.

I can get 20+ mpg in my Dodge diesel putzing around N WI empty not in a hurry or a personal worst record of 9 mpg only pulling a 3klb cargo trailer ( 80mph westbound into a nasty headwind for hundreds of miles will do that).
Anything that burns unleaded I figure 8mpg one I hook any decent size trailer to it.
I can’t sit in the truck lane crawling along at 55-60 mph though unless the truck or the load won’t accept faster speeds.

[agesilaus]

"Third, add the cost of DEF"

That cost is microscopic compared to the other costs, it's a fraction of a cent per mile. I just added a $7 bottle of DEF after more than 4000 miles of mostly towing this summer.

You also did not add in the higher resale value of a diesel and it's longer life and engine brake. That engine brake is a major factor in my mind.

But the main point is none of those points, it is where you are towing. In the flatlands like the country east of the Mississippi a gasser is fine. In the mountains is where the diesels shine.

[Lwiddis]

Your F150 should do much better. I get 12 to 13 pulling 5000 pounds but am rarely over 55 mph.

[theoldwizard1]

wowens79 wrote:
Unless you are towing 50k miles a year the cost of the diesel will never be recouped in fuel savings. I think that Eco is probably about the perfect setup for you trailer.

Concur !

First, the days of great fuel economy with diesel engines are long gone !

Second, around where I live, diesel fuel is at least 20% higher cost.

Third, add the cost of DEF.

Fourth, diesel engine oil changes with filters are expensive ves new spark plugs every 100k miles.

[Me_Again]

I went from towing a 16k high profile 5th wheel to Arizona and back twice to a 8K TT twice there and back. Mileage between them was almost the same the first year I towed the smaller TT. Last winter I towed the smaller trailer without T/H on and sped up to 65-66 MPH vs the 60 MPH I towed before and allow the truck to shift into 6th gear. Mileage went up ^^^^^^ 1.5-2 MPG. In T/H it will not shift to 6th until over 65 MPH.

I run things through my mind all the time and one is do I really need a SRW 3500 to tow a 8K TT back and forth to AZ from NW WA. The answer keeps coming out the same. Why give up a truck you really like and that tows the TT effortlessly. I do not even bother installing the sway control anymore as the 8K trailer does not push around the 8500 lb truck at all. I do use the equalizer bars.

The diesel trucks have a big advantage going down mountain passes in their exhaust brake.

[1320Fastback]

7-9 is completely in the EcoBoost towing mpg range. The engine is either in Eco mode or Boost mode. Its one or the other, never the both at the same time and when it is in Boost it is dumping fuel in. I didn't catch the towing speed either but the faster you want to pull that parachute the more boost and more fuel your going to use. A EcoBoost towing at 75 will be getting 7mpg.

[mtofell1]

Grodyman wrote:
It gets 7-9 mpg towing an untralight 4500lb trailer

I'm sensing a litte, "cooking the books" here. I get 9 with a less efficient gas engine pulling an 11,000# 5th wheel out west in the hills. Your Ecoboost has to do better than 7-9 with a 4500# trailer.

It sounds like the diesel will make more sense for range between fuel stops but the money saved on fuel alone will never pencil out in any reasonable amount of time.

[jdc1]

My 2001 Dodge Ram 2500 5.9 diesel saw 19mpg empty, 13 towing 7,500 lbs.
My 1997 F250 460 gasser got 7-8mpg empty. Forget towing....too expensive.
My 2000 F350 7.3 diesel sees 15-16mpg empty, 12.5 towing my 8,000 pound 5th 5th wheel..

[Turtle_n_Peeps]

About 30% better mileage with a diesel all things the same. I got 9-10 with my gas and 12 with my diesel. Same trailer, speed, weight.....bla, bla, bla....

[wanderingbob]

My neighbor yesterday was telling me how foolish it was to drive a diesel truck as we were riding down so he could buy a $ 400 ice chest . I guess we all just need to do what feels good !

[wanderingbob]

A lot of the extra cost to buy a diesel will be recouped when you sell or trade . A used 5 year old diesel will bring 4 or 5 thousand more than a gas truck , check comparable trucks on Blue book .