My 2013 RAM 2500 diesel and my 2020 RAM 3500 dually diesel HO/Aisin got about the same mpg (10-11) towing my 12k 5th wheel. Unloaded my 2500 would approach 21 mpg. My dually will approach 19 on longer trips. Unloaded I run 78 mph, loaded 65-70 mph depending on traffic.
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Towing MPG
- Thread starter Jared2500Ram
- Start date
This is about what I get also. They drink def when towing.
I know this will not go over well with most. But if better MPG is what your looking for. Its easy, not hard to get. Plus this option is in the truck from the factory. That skinny peddle under the right foot holds that Magic. Anything over 55 MPH, your dropped MPG like a rock. Yes you can delete and tune until your old and grey . Spend what $5000.+ or more.
How many MPH better would you have to get to show a return? Slow down from 70+ to even 62 MPH, watch that miles per gallon climb. Yes it works! Used to run OTR, back when most here was not even a twinkle in your dads eye's. Even back in the mid 80's when nation wide speed limits were 55. Yes even on the interstates it was 50 or 55 MPH. As a fleet back then with mechanical engines. Our 120 trucks averaged 6.725 Miles per gallon. That with idling most nights for heat or AC. When we had AC.
Not saying you can't run 70 MPH. Just saying ask your self if that extra few minutes you think your saving is worth the lower MPG? If it is be happy and live with even 7 MPG if that's what you get. But please don't blame this truck or that maker for your lead foot.
How many MPH better would you have to get to show a return? Slow down from 70+ to even 62 MPH, watch that miles per gallon climb. Yes it works! Used to run OTR, back when most here was not even a twinkle in your dads eye's. Even back in the mid 80's when nation wide speed limits were 55. Yes even on the interstates it was 50 or 55 MPH. As a fleet back then with mechanical engines. Our 120 trucks averaged 6.725 Miles per gallon. That with idling most nights for heat or AC. When we had AC.
Not saying you can't run 70 MPH. Just saying ask your self if that extra few minutes you think your saving is worth the lower MPG? If it is be happy and live with even 7 MPG if that's what you get. But please don't blame this truck or that maker for your lead foot.
H3LZSN1P3R
You're doing it wrong
anything over 2k rpm you can watch the MPG take a dive at anything over 55-60
kobra
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Not that way at all for my truck and trailer. At 60-62mph my truck will shift down a gear and run at 1800-1900rpm. Running at 65-68mph, RPM is 1600-1700 and really seems to find a sweet spot. The mileage is almost identical, with the faster speed often getting slightly better.
I'm towing a full profile Montana 5th wheel at almost 17k lbs. Just in the past couple of weeks on one stretch I had a headwind on bad roads and drove 58-62mph and got 7-7.5mpg. Another stretch, I had a tailwind on good roads and drove 68-70mph and got over 10mpg. So for my truck and trailer, wind will make FAR more difference in mpg than does speed.
When we sometimes travel 600 miles in a day, we could save 1.5 to 2 hours on the day. Even our typical 6 hour trip could save well over an hour of time at 65-68mph vs 55mph. That's a lot more than a few minutes. And, as above, a few mph extra may actually drop a gear, get the truck right into its torque band, and return similar mileage.
Now, maybe for others with much smaller, lighter and less wind resistance rigs there may be significant differences if slowing down. But my sweet spot is 65-68mph, and it was similar with my prior 2500 towing a mid profile 13k 5th wheel.
Brad
Jacob
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I agree with this. Anything less than 65 and I think the rpm is getting low. I typically tow 65 to 75. I would think the mpg is a lot better at 65 than 75. I usually just drive as fast as I think is safe for the road conditions.
McHenry2500
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Just got home about a week ago from a 2,000 mile roundtrip towing my 26' gooseneck with 2 SXS's on it. Averaged about 10.5-11MPG the entire trip.
I did notice my mileage was about the same from home (630' elevation) to the cabin (9,200' elevation). I assumed the higher altitude would have more of an effect.
Side note; diesel was near the $4/gallon price in Durango area but we still have $2.70ish/gallon here in Texas.
I did notice my mileage was about the same from home (630' elevation) to the cabin (9,200' elevation). I assumed the higher altitude would have more of an effect.
Side note; diesel was near the $4/gallon price in Durango area but we still have $2.70ish/gallon here in Texas.
I will agree some trucks will do better with just a little more speed. But a brick is only going to get so much. Then extra speed = wind resistance. And speed does not overcome that.
Just got my 22 Big Horn Dually ordered today. So looking forward to the low MPG club. But we will only run 4 or so hours per day. Retired were not in a rush. Just take our time and see the country.
Going from this to the 22.
1995 Kenworth T600 only get 4000+ miles per fuel up. But it does hold 470 gallons.
2005 Kodiak C5500 with a 275HP 5.9 Cummins hooked to a 6 speed Allison. Enjoy both trucks with the 5th wheel. But were going back to a slide in truck camper.
kobra
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Interesting move! Often people are moving the other way, bigger and bigger.
I think the key is that these new rigs are not bricks, but actually are very aerodynamic for their size. I wish I knew where to find data, but in general I think we can agree that the worse the aerodynamic efficiency, the more that speed will increase drag resistance - which affects power required and energy inputs (ie fuel burn). Which of course is why an F1 car today can travel faster with smaller engines yet get more laps between refueling than they were a few years ago.
I do really think you are right that 55mph was a "sweet spot" for the rigs you ran in years past, but I really don't think that applies the same to modern rigs with the smoother aerodynamics. I think it's a lot of things going on, including aerodynamic drag, engine design, gear ratios and final rpm, etc, etc... and that all of those things (and likely more) are responsible for the "sweet spot". There is nothing inherently "better" or "magic" about 55mph... some rigs will be most efficient at 55, others at much higher speeds. Or, one could argue there are certain loads with certain rigs where 55mph would be way too fast for peak efficiency.
So, in my recent experiences with 2x RAM/cummins trucks and 2x 5th wheels, there was very little difference between slower highway speeds and faster ones. Now, if I compared 40mph with 80mph I'm sure I'd find a big difference. But I really don't think there is a significant difference in mileage between 55, 60, 65 or maybe even 70 mph with the combinations I've towed with in recent years. Other trucks, towing other rigs, will have different results; for example, likely for your HD and MD trucks, the numbers I'm sharing wouldn't be the same at all.
To be clear, I'm not arguing at all that more speed equals more drag which requires more energy. Rather, I'm sharing the experience that within the range of speeds we are talking about, while using a RAM/cummins and a 5th wheel trailer, the differences are very small, AND that other factors such as wind speed and direction will make more of an impact on overall mileage. (worst is the head on quartering wind; a dead on headwind will have less impact).
I'd recommend experimenting with your rig when you get it. You may find faster speeds work well, or you may find it really does negatively impact mileage. Either way, drop back and share your experiences.
Brad
I will run with traffic when pulling my 5th wheel camper. I will run the 70 MPH speed limit if traffic allows. I will slow down when traffic or road conditions dictate. Honestly, If I have to be concerned about fuel economy and fuel costs for financial reasons, I would sell my truck and trailer.
Gondul
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For me it isn't so much fuel economy/cost, but how far I'm going to be able to go and make convenient (to me) stops for fuel/breaks.
kobra
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Agreed, but given that mpg changes with a lot of things out of our control - such as wind and terrain - I changed out to a 50 gallon internal Titan tank.
See my post above where wind difference was from low of ~7mpg to ~10+mpg with the same rig - do the math on the difference that will make in fuel stops with the smallish OEM tank. Now with the 50 gallon tank, on short to medium days (200-400 miles) I fill up when empty and don't need a fuel stop midday. Or, on longer days, I expect I may need 1 fuel stop instead of 2 stops (or worse case I've had to make 3 stops with the OEM tank!).
Traveling out west where we frequent, there was no way with the OEM tank to slow down enough to make all the stops when convenient. Worse case, I've had to make a stop a half hour before my final stop because I wasn't sure I would make it, so I took whatever price I could get. I once paid 60 cents / gallon more, and have often had to pay 40+ cents more than if I could have waited a bit more.
So, in my experience, adding more fuel capacity was far more key than the difference of slowing down to try to stretch the fuel economy. YMMV, and likely does with different rigs or less variance from wind and terrain.
Brad
Exactly, if you just drive down to the local park, then you probably aren't too concerned with fuel economy and having to plan fuel stops.
Gondul
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Entirely agree environmental factors impact mileage... driving across Alligator Alley in FL @75mph into a headwind knocked me back 2mpg
Once we do more long distance towing I will have to get some way to transport more fuel.
I'd prefer a replacement tank, but with the gasser looks like it will be an in-bed though I'd rather not lose the bed-space, it is what it is.
Eatonpcat
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For what I spent on my limited in Canadian funds the fuel is the last of my worries. I'm more concerned about maintaining it since I don't do any of that myself.
Are prices more in Canada or is the big difference the currency exchange rate?? I could probably figure this out, but it is easier to ask...I was called lazy on the forum yesterday, maybe there is some truth to this!!
I think the price is probably a combo of dollar value and basic costs, its hard to figure out for 2 reasons, the dollar is always changing and our option packages are a little different than the US's, anyway without Chrysler incentives and negotiated price the list on my Limited with my options listed in my signature is approximately $108,000 PLUS TAXES!. So my 50 US gallon tank would cost $250 or so to fill , and to me that's not bad for the added convenience. I'm more worried about the cost of changing my fuel filters and oil change expense. Here is the link to the window sticker https://hdrams.com/forum/index.php?...-and-discuss-your-order-here.2622/post-107934
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