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2021 Ram 2500 Tradesman Crew Cab 6.7 L Turbo Cummins 3.73
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Discussion Starter · #1 ·
We just got back from our 2nd RV trip with the new truck. Same RV trailer, our 21 foot Coachman, all loaded is about 4500 lbs, along with the stuff in the box, fuel and bodies can add another 2000 plus lbs. This was going to the Kenai River at the Russian River Ferry parking lot, 150 miles one way. With the mountains and almost constant wind, it may take a few trips to get the "mean average" for the Cummins. And for this piece of hwy, its not the best for checking mpg anyway.

The Ecodiesel I used to own is still the champ of mileage. Same run as before, but I would get 13.5 - 14 mpg on this run, depending on the winds, which can be ferocious along Turnagain Arm.

With this Cummins, speed really kills mileage towing an RV. As far as I can tell so far with the "lie-O-meter", is there is at least 3 mpg difference between 55 mph and 65 mph. But we all know this when pulling a parachute, but it seems more noticeable with the CTD then the Ecodiesel.

The new 2021 CTD HD gets around 13 mpg towing, this last trip was 13.2 mpg, better then the first tow trip, where I got 12.9. A smidge less then the Ecodiesel did.

While this load is nothing to the 6.7, I have to hand it to the 2017 1500 Ecodiesel, it can sure haul a load very well for less fuel.

But I expected a little better mileage from the Cummins, at least on par. But it is also still very new with almost 3000 miles, and mileage may improve over time.

The Cummins has power to spare. Everywhere I go, it's in 6th gear with this load. Even going up the 7% hill just past the Hope cut off, it's in 6th gear at 60 mph towing a trailer. Torquey beast, its really quite amazing. The box is deep, you can't see anything in the back, but its full.

The built in Trailer Brake Controller works really nice, I like the foot pedal pressure actuator, just wonderful. Once I got it set up, I forgot about it. With the exhaust brake and tow/haul mode involved, I haven't had to use the brakes much. The Trailer Light Check routine is also very handy. Of course the back up camera is top notch for getting under the hitch, one shot, you're in. The whole rig feels stout and safe.

Overall I'm happy with my purchase, the Tradesman is a comfortable truck, with adequate features and ample power. I like the reliability factor of the Cummins engine too, really my main interest in buying this truck. With all the round-a-bout way out there driving we do, I need some piece of mind.

Turnagain Pass (1000 feet ele.)
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2016 SLT 4x4 Quadcab 3.53 with a cap
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I would say that with only 3000 miles you have a fair distance to go before it's broken in and then the mileage will increase by 2-3 mpg. My old 2004.5 2500 HO didn't start to get better mileage until about 45-50K miles. Pulling a 22" trailer I could easily get 20 mpg CDN, around 16 US.
 

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I do t know about the break in time. Dads ‘18 started getting about the best it ever has after the first tank of fuel and it’s at almost 60,000 now.

I wonder what the difference is between the Aisin and 68rfe, dads won’t hold 6th gear with the cruise on towing our boat much less the TT. His has 3.42 gears what does the 2500 have?
 

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2021 Ram 2500 Tradesman Crew Cab 6.7 L Turbo Cummins 3.73
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Discussion Starter · #4 ·
I do t know about the break in time. Dads ‘18 started getting about the best it ever has after the first tank of fuel and it’s at almost 60,000 now.

I wonder what the difference is between the Aisin and 68rfe, dads won’t hold 6th gear with the cruise on towing our boat much less the TT. His has 3.42 gears what does the 2500 have?
I have the 3.73 finals with smallish tires (245/70R/17 E) that are about an inch less in diameter then the Ecodiesels 265/70R/17, probably giving me a bit more torque.

Going up these hills in 6th gear is somewhat strange when I think about the old 1994 GMC half ton 350 ci 4 speed screamer in 2nd gear up the same roads, same load.

I have the 68RFE. It never gets very hot towing, around 168 degrees F.

Technology is wonderful!
 

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Discussion Starter · #5 ·
I would say that with only 3000 miles you have a fair distance to go before it's broken in and then the mileage will increase by 2-3 mpg. My old 2004.5 2500 HO didn't start to get better mileage until about 45-50K miles. Pulling a 22" trailer I could easily get 20 mpg CDN, around 16 US.
16 mpg would be wonderful, and kind of what I anticipated.

I might try forcing 5th gear on the steep hills and see how that effects mileage.

Like I said above, it's the worst run for figuring out mileage. My Ecodiesels "mean average" for towing our load was about 14.5 mpg. Down in Louisiana, with a heavier load than normal, and that dark rich stinky #2 diesel straight from the tap, one clear and windless day on flat as water roads, I got 16.4 mpg on the Ecodiesel. And the worst case was filling up with clear #1 diesel in upper BC with lots of hills, I barely made it to the next town at 10.5 mpg.

That really shows how much driving up and down mountains can effect mileage. And fuel matters too.
 

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Sourdo.... When pulling my empty gooseneck 5k being flat I’ll still only get 14mpg .... Pulling 20k plus 9-10 mpgs.. It’s a very predictable in regards to mpgs...
Cummins is more than twice the displacement of the EcoDiesel,still have to feed all the ponies...Regardless....
There is a trade off EcoDiesel vs Cummins, Fuel economy or Reliability?
I Loved my EcoDiesel’s fuel economy , My love affair ended at that point...

You can play with Tow haul , I’ve found lock out 6th gear Full exhaust brake and be ready to feather the throttle if you apply the foot brake, not to start transmission down shifting..

If you try to force 6th gear and non tow haul transmission will want to shift around and start raising temperatures, But you will get better mpgs... I like to experiment and tinker as well...IMOP not worth the additional transmission shifting and elevated temperatures... Trying to save a couple bucks in Diesel fuel....

IMOP Tow haul, Lock out 6th gear Enjoy the worry free trip... It is what it is ...

My truck has the Aisin transmission, 3.42 gears 2016 , Comparisons could be different...
 

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Discussion Starter · #7 ·
Sourdo.... When pulling my empty gooseneck 5k being flat I’ll still only get 14mpg .... Pulling 20k plus 9-10 mpgs.. It’s a very predictable in regards to mpgs...
Cummins is more than twice the displacement of the EcoDiesel,still have to feed all the ponies...Regardless....
There is a trade off EcoDiesel vs Cummins, Fuel economy or Reliability?
I Loved my EcoDiesel’s fuel economy , My love affair ended at that point...

You can play with Tow haul , I’ve found lock out 6th gear Full exhaust brake and be ready to feather the throttle if you apply the foot brake, not to start transmission down shifting..

If you try to force 6th gear and non tow haul transmission will want to shift around and start raising temperatures, But you will get better mpgs... I like to experiment and tinker as well...IMOP not worth the additional transmission shifting and elevated temperatures... Trying to save a couple bucks in Diesel fuel....

IMOP Tow haul, Lock out 6th gear Enjoy the worry free trip... It is what it is ...

My truck has the Aisin transmission, 3.42 gears 2016 , Comparisons could be different...
Yea, I'm kind of getting the "it is what it is".

I'm on a fine line with the 3.73,s and 245 tires, probably why it runs in 6th gear so easy. Someday I'll see some 265/70R/17 E,s on the Big Kahuna. Those are an inch taller.

But on those steep grades of 7%, it just don't seem right to be in 6th gear. It really amplifies the power of the 6.7, I love it. I'll try locking out 6th when I'm in the hills and see what transpires. One of my issues is on the Seward Hwy, it's 65 mph two lane road, so I keep up with the flow of traffic. It's fairly busy as the only road in and out of the Kenai, and I don't want to be the bottleneck. I always thought 58 mph was a good towing speed for any of my previous trucks, and that seems to be true for the CTD, if you're after efficiency. There is a big difference from 55 mph to 65 mph.

As for reliability versus mileage? I'll go reliability anytime. I read about one too many blown up Ecodiesels, reluctor wheels, EGR cooler, this, that, while the Cummins Gen 5 forums, I read nothing. Nada, nyet for problems. Oh I know, if I dig I can find one or two issues, ie, the CP4 HPFP. That recent thread about the Cummins that blew a hole in the block is the ONLY blown up CTD I've seen to date after months of looking and thinking about buying a HD CTD truck. This lack of issues was very apparent and very attractive to me. When you're in-between Lake Watson and Fort Nelson pulling an RV, you don't need any hanky panky. I felt like I was running the odds a little too far too long.

The final straw was I could not find an effing dealer to put in the new EGR cooler, it was pissing me off after a year of yadeyadeya bullshit. This almost got me looking at Duramax's, but Chevy dealer mechanics is another story.

Or cave in and sell the damn thing and buy a THE new truck of my dreams, a real inline six holed turbo charged Cummins diesel power demon!

Were going to do the Dalton Hwy to the arctic this year, it should be an awesome trip. It is over 800 miles one way. I'll get a good measure of mileage on that trip. Guide to the Dalton Highway | Livengood to Deadhorse

I appreciate the reply's and experiences, the true value of the forum, trading info.
 

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I think I was getting that 12 to 13mpg towing 10k with our loaded out 5 horse on the prairies. Thats at or above highway speed. My wife let's it go onto 6th but I lock out. Mind you we have 3.42 gears. It seems super happy around that 1800 rpm.

I want to say we are close to 10mpg when loaded to the hilt with hay at highway speed.

I use a comparison to what my gasser 2011 1500 hemi got. Same circuit to get hay, almost identical tank size. My 1500 could move six 1600 pound bales at max 80km/h using just over 3/4 of a tank. My 3500 can do ten 1900 bales at 100km/h using less than 3/4 of a tank.

While your eco good do slightly better mileage with that trailer, wait until you move up to a trailer that your eco could never haul. Then the fuel mileage really isn't an issue. That and hauling heavy up hill with no worry of oil, trans and coolant temps spiking and having power to spare.
 

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IMOP Tow haul, Lock out 6th gear Enjoy the worry free trip... It is what it is ...

My truck has the Aisin transmission, 3.42 gears 2016 , Comparisons could be different...
That’s what I do with dad’s ‘18 and 3.42’s / Aisin. Drives me nuts when riding with him and he sets the cruise in drive no tow/haul and it shifts on every rolling hill/overpass.
 

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Discussion Starter · #10 ·
That’s what I do with dad’s ‘18 and 3.42’s / Aisin. Drives me nuts when riding with him and he sets the cruise in drive no tow/haul and it shifts on every rolling hill/overpass.
I've liked the Tow/Haul mode for city driving ever since the 2011 Silverado. Holding a lower gear longer was the best effect. For the Ecodiesel, along with city driving, Tow/Haul mode was helpful to warm it up. One of the other nemesis of the Ecodiesel, hard to get hot in the winter. This new CTD gets warm very quickly, I would say 1/3 (or less) of the time the Ecodiesel would take to get to full temp. I really like this quite a bit more then I would of known. The vents are blowing warm air fairly quickly.

I find the new 2021 2500 CTD is much the same for city driving with Tow/Haul on. And along with using the Auto Engine Brake, I practically never push hard on the brakes. Sounds cool too.

I really can't find a fault with this truck, but that the bed can't accommodate my quad with the tailgate up. As long as this truck don't leave me stranded, I'm golden!
 

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2019 Ram 2500 Cummins - EX Ecodiesel owner.
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Been pulling the same toy hauler with my Cummins as with the Ecodiesel. 1 mpg less fuel economy with the Cummins if I tow at the same speeds. There-in is the rub.

The Cummins easily goes faster pulling the trailer than the Ecodiesel did. So, I tend to go faster. That blows tires on the trailer and drops the fuel mileage. If I mentally could control myself and just do 65 mph tops, my take on the mpg thing is it would be closer to the Eco. Yet going up mountains slower, like you were forced to do with the Ecodiesel, is not factored in. Top speeds are not the only "drinker of fuel" . Where I struggled to pull steep grades at 35 mph with the Ecodiesel, now I easily pull at full traffic speeds. That has to cost me fuel mileage.

Leaving for a month with that toy hauler and heading to the Carolina/ Va. mountains.There is a motorcycle rally and motorcycle rides to do plus general goofing off. Time for my Cummins to drink some fuel under load.
 

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Showed this to my wife. Holy shit. Sorry for the statement but not really. No way will you return the same if taking that run. Smashed and trashed will be the motif.

That sure could be an adventure.
 

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Discussion Starter · #13 ·

Showed this to my wife. Holy shit. Sorry for the statement but not really. No way will you return the same if taking that run. Smashed and trashed will be the motif.

That sure could be an adventure.
I was shocked to learn the company I retired from, has been paving that road for the last two years, and is supposedly in good shape.

And it is also one road we haven't been on yet, so later next month we're going to do it. The Canada border remains closed, the campgrounds remain empty.
 

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Captain whats the MC ralley? I could be in for that. Dalton Hwy.. not so much.
Sourdo Seems the world is opening from Covid restrictions. Thursday we leave for Greece.
 

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Discussion Starter · #15 ·
Captain whats the MC ralley? I could be in for that. Dalton Hwy.. not so much.
Sourdo Seems the world is opening from Covid restrictions. Thursday we leave for Greece.
The plan is to drive out of here for the winter providing the border is open. IF it isn't open it's going to suck big time.

Enjoy your trip!
 

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2016 Laramie Limited Crew Cab 4x4 with Deleted Air Suspension and GDE Hot Tune. 262,000 KM.
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I would say that with only 3000 miles you have a fair distance to go before it's broken in and then the mileage will increase by 2-3 mpg. My old 2004.5 2500 HO didn't start to get better mileage until about 45-50K miles. Pulling a 22" trailer I could easily get 20 mpg CDN, around 16 US.
I agree.
My 2020 F150 3.5 Ecoboost work truck has improved from 14.5 L/100km when new to 12.2L/100km now that it has 45,000kms on it.
 

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I think I was getting that 12 to 13mpg towing 10k with our loaded out 5 horse on the prairies. Thats at or above highway speed. My wife let's it go onto 6th but I lock out. Mind you we have 3.42 gears. It seems super happy around that 1800 rpm.

I want to say we are close to 10mpg when loaded to the hilt with hay at highway speed.

I use a comparison to what my gasser 2011 1500 hemi got. Same circuit to get hay, almost identical tank size. My 1500 could move six 1600 pound bales at max 80km/h using just over 3/4 of a tank. My 3500 can do ten 1900 bales at 100km/h using less than 3/4 of a tank.

While your eco good do slightly better mileage with that trailer, wait unt inil you move up to a trailer that your eco could never haul. Then the fuel mileage really isn't an issue. That and hauling heavy up hill with no worry of oil, trans and coolant temps spiking and having power to spare.
My key take aways pulling the same coach with the eco and Cummins is the following:
*The eco with air suspension was an incredible tow vehicle. It took the abuse and frankly overloading and never complained. A marvel of engineering. I was exceeding it's rated numbers consistently in rigorous conditions.
* I'm just at 50% or less of the truck capability for the Cummins.It is in a nutshell a much more relaxing experience. I don't even use sway or dist control. I do have a gen y torsion hitch. Just drop it on the ball.
*The Cummins is a monster, In mountainous conditions is where it shines. Up and down.
*I see it as purpose built tool and it needs to be worked. I feel just using it as daily driver is ok but not what it does best. A half ton is much more qualified for that task.
Mileage was never a consideration. I always wish both had a bigger tank!
 

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Captain whats the MC ralley? I could be in for that. Dalton Hwy.. not so much.
Sourdo Seems the world is opening from Covid restrictions. Thursday we leave for Greece.
Moto Guzzi rally in southern Virginia near Meadows of Dan on the Blue Ridge Parkway. Pam does not like my new V9 Roamer until I get a larger rear rack and backf=rest for her so we are taking the FatBoy.

89772


Canadian border scheduled to open July 21st. Heard that on the news.
 

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Looks like a nice comfy street bike. I'd have to get a backrest & rack and take the Roamer. Wouldn't seem right to leave her home when going to a Guzzi rally. Lol bet its a lot different than any Harley rally.
 
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I like this talk, gets me thinking back. My 1500 was a beast for what it was. It did return respectable fuel mileage on flat tows with the horse trailer but as I think back, I never really went more than 110km/h in optimal conditions.

Now my 3500 does 110 everywhere. Doesn't matter what weight, just keep the revs in the sweet spot. That brings me back to a story; the family and I were off to pick up a horse so we had the 5 horse unloaded but our usual crap in the tack room. Maybe 6000 pounds total. Was loafing along in 6th when I came up to a slow moving truck. Well 115 isn't slow.... I dropped it to 5th, got her at about 1800rpm and a bit of boost. Once safe to pass, gave her half throttle. She held 5th and I blew by. Kept on to give lots of clearance and pulled back into my lane doing 150. Sweet Jesus! That was a touch on the fast side but man can that truck haul. She's quicker now after the delete....
 
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