6.4l terrible mpg

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Vicman

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Valdese, NC
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2016 Power Wagon
Engine
6.4 Hemi
16 PW, 35" Cooper STT knobbies, 80K miles, owned it since birth. Stay under 70 (69 mph to be safe) I get as high as 17mpg on the highway 12-13 kicking around town.
You bought a huge truck with a huge engine, if you can't pay don't play.
 

folashade96

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Nv
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2021
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3.0 ecodiesel
I feel for OP. Sure it's a 2500 with a 6.4 V8 on 35s, but if we're being honest, 10 MPG on flat ground unloaded, even if it is a 2500 is bad. When I had my TRX i managed to squeeze out 17 on a road trip doing 72 between Reno and Vegas. Shoot my Excursion V10 gets what he's apparently getting and I idle excessively.

The only thing I can say is maybe the speedo wasnt recalibrated and maybe he's going faster than he thinks. Other than that I have no idea what to say.
 

Willie Mosher

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6.4 gas
I have 2018 4x4 2500 6.4 gas ⛽
6 speed transmission.
W 275/70/18 all season tire, (OME style)
@ 70 mph I get 18.3 mpg,
City +\~ 10 mpg,
Tow 4500 camp trailer @ 68 mph
Get @+\~ 10 mpg.
 

About tree fiddy

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Woodbury, Georgia
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2021
Engine
6.4
My ‘18 PowerWagon on 35” Yokohama Geolander X-MTs definitely hurts at the pump! In 29,000 miles, I’ve had 6 tanks over 10mpg, one more over 11mpg, and one more over…gasp…12mpg! Pulling my toyhauler and gear(8500lbs?), 6.5+/-! The few times pulling the toyhauler has averaged a hair over $1/mile!

Not complaining…love driving it, wheeling it, and hauling with it!

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Nice. How long is that toy hauler hitch to bumper? I'm upgrading my trailer soon from a 28 to a 33 footer.
 

RichieW13

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Thousand Oaks, CA
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2014
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Hemi 5.7
I have a stock 2022 Ram 2500 Crew Cab Short Bed 4x4. I have about 4,000 miles on it.

On long highway trips, the best I've seen is 14.6mpg (calculated).
Around town I'm usually in the 10-11mpg range.
Towing my 7,200 pound trailer I get 7.9mpg.

I have a 31 gal tank, so my driving around town weeks I can't quite make it to 300 miles/tank without getting nervous about running out of gas. (I hate how early the "fuel tank low" notification comes on - at about 1/4 tank.)
 

Bearcatrp

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RichieW13, it gets better after the motor gets broke in. You have a 8 speed tranny, right?
 

runamuck

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seems like the tongue wt. of a 7500# trailer would be more than the cargo cap. of that eco dsl 1500..I know my laramie tops out at 1324# so that eliminates most of the trailers I have looked at in that size range. our current trailer is 6000# with a 600# tongue wt. and with wife and fuel I am almost maxed out or I would be trying to score a new eco dsl 1500 instead of shopping for 2500's.
 

Whiskey13

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Power Wagon equals big rock slung down highway with big motor. Love mine and know for sure my gas mileage is never going to improve but I'm okay with that
 

OC455

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5.7 Hemi Big Horn, 6.4L Hemi 3500 Longhorn Mega cab
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Took a road trip to Lake Placid this afternoon. On the way back I filled up with 89 octane. Been filling up with 89 now.

The range showed 450 mile for 32 gallon tank. I've never had that before even with the slow speed being driven.

The lie-O-meter showed over 14MPG...first time that's happened. I used a little over a 1/4 of a tank. The trip was 145miles from my house to Lake Placid.

I was mostly averaging above 60MPH in the high peaks of the Adirondacks. I will say the Longhorn does better on the 89.
 
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metro ATL
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6.4
If we're paying $4 a gallon gas and diesel is $5: when gas gets 8 mpg towing, and the diesel gets 10 mpg, we're paying the same per mile. Even if you go from 6 mpg towing to 10 mpg (gas vs. diesel) it's a .50 cent difference. Over a thousand miles that's $500, but if you add diesel's extra maintenance, oil, DEF, and price of admission - the line between them is about even...no?

Reading the lowest mpg here towing, IMO, the two are still even. Diesel can tow more and get +/- 20% more fuel efficiency. Gas offers lower cost daily, upfront $, and the easiness of a gas engine. They're even if you're not towing 15K+ loads. I asked a local with basically the same set-up as I got what he was getting towing 10K daily (heavy equipment), and he said "10."

Furthermore, I don't have nor have had a single high-performance car I drive that gets over 15 mpg with premium - most are 9-12 mpg. Sure, if I drove them slowly and with care, I could get into the twenties on the highway, but it's just not happening. I view an HD truck the same - they're not meant for fuel economy.


*ABSTACT*
If diesel were $2.5 a gallon, parts were available, no shortages, low upfront problems, and no possible diesel fuel shortages - then it would be a no brainer to go with diesel. My question is, when the 'real shortages' start happening, what will citizens do when diesel parts, oil, and fuel only goes to trucks for transporting goods? This is plausible, and even if we start manufacturing oil to fuel again in the US, it will take years to stabilize from where we're at. It's a reality - not a political statement. Truth is, I really wanted a diesel, but not in this economy. In the end, I needed reliability, parts, and fuel more than the extra "umph" right now.

@OC455 Did you not get 14 to the gallon? A little more than an 1/4 tank is 10 gallons? 10 gallons @ 14 = 140 and you got 145 total. Considering the terrain your DRW truck did well. Also, thanks so much, for telling/helping me to get the 35 over the 25.
 

OC455

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@OC455 Did you not get 14 to the gallon? A little more than an 1/4 tank is 10 gallons? 10 gallons @ 14 = 140 and you got 145 total. Considering the terrain your DRW truck did well. Also, thanks so much, for telling/helping me to get the 35 over the 25.
I haven't done the actual hand calculated mileage yet, going to fill up next payday. The lie-o-meter as it is called, was over 14MPG. I've compared hand calculated to the MPG on the truck's gauge on the EVIC and it is a couple tenths off (lower).

No worries on the choice.
 

Doug Ram

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Central NY, AKA Upstate NY
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2021
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Eco Diesel _3.0
seems like the tongue wt. of a 7500# trailer would be more than the cargo cap. of that eco dsl 1500..I know my laramie tops out at 1324# so that eliminates most of the trailers I have looked at in that size range. our current trailer is 6000# with a 600# tongue wt. and with wife and fuel I am almost maxed out or I would be trying to score a new eco dsl 1500 instead of shopping for 2500's.
What year is your Laramie? In 2020 they upped the cargo capacity a bit. My 21 ED crew cab Big Horn has a cargo capacity of over 1600#. I tow a 6,000 lb trailer all over the country with dog, wife and a bed full of generator, 5 gallons of gas, extra propane tank, skis or kayaks, cooler, and other junk. With all this aboard for our last trip I weighed it all at cat scale and was under vehicle limit with 100lbs to spare. Even with full tank (33 gallons) of diesel fuel. I don't know what Ram does to the Laramie to cut the cargo capacity to less than 1500#, but that your truck ought to called a 1300. This is the primary reason I went with Big Horn ED -- added cargo. I would have gone with a Tradesman ED, if I had to, to keep 1500# cargo capacity.
 

runamuck

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Doug Ram my laramie 1500 is a '19. I guess the few extra bells and whistles on a laramie are heavy ones. mine weighs 5960# with just me and 1/2 tank of fuel.
 

Bearcatrp

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Hemi 6.4
Yes, 8-speed. I'm skeptical that my gas mileage will change much after 4,000 miles. How much more breaking in could happen?
Just went over 10,000 miles and my second oil change. Was averaging 11-12 mpg under 5000 miles. Am up to 14 mpg average. Of course your miles may vary if your heavy on the foot. Nice thing about the 8 speed is not much throttle needed as it goes through the gears to speed up. No regrets going gas with this 8 speed.
 

RichieW13

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Hemi 5.7
Just went over 10,000 miles and my second oil change. Was averaging 11-12 mpg under 5000 miles. Am up to 14 mpg average. Of course your miles may vary if your heavy on the foot. Nice thing about the 8 speed is not much throttle needed as it goes through the gears to speed up. No regrets going gas with this 8 speed.
I hope that happens for me.
 

RacerRon

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6.4 Hemi
I also have a 2021 2500 6.4. My mileage started improving substantially once I hit 20,000 miles. Is currently sitting at almost 17 average with mixed driving. Idle time will murder the average fast. Stop lights and drive through lines kill it.
 

retired

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I also have a 2021 2500 6.4. My mileage started improving substantially once I hit 20,000 miles. Is currently sitting at almost 17 average with mixed driving. Idle time will murder the average fast. Stop lights and drive through lines kill it.
keeping it around 70mph and not trying to launch off the line helps too. Even when mine was new I have never gotten under 12mpg except when in Moab crawling around. Sure if I drive 80mph I can get 14mpg but drop down to 70mph and I am high 16's to mid 17's. Unless I am driving on Minnesota gas then I am lower.
 
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