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The OP doesn't mention what the rear differential ratio is on his truck. Wouldn't that make some difference? Between say a 3.25, 3.55, or 3.92 :1? Seems to me that a truck with a 3.92 running at a steady 60 mph will be turning a higher RPM than one with a 3.25 running a steady 60 mph. I suspect that a sustained higher RPM would, over time at least, result in somewhat reduced fuel mileage. Not sure if it would make that much difference though.
 

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The OP doesn't mention what the rear differential ratio is on his truck. Wouldn't that make some difference? Between say a 3.25, 3.55, or 3.92 :1? Seems to me that a truck with a 3.92 running at a steady 60 mph will be turning a higher RPM than one with a 3.25 running a steady 60 mph. I suspect that a sustained higher RPM would, over time at least, result in somewhat reduced fuel mileage. Not sure if it would make that much difference though.
3.55 and 3.92 are the only options. They're so close together it doesn't make much difference at all.
 

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So, mine is a 2016, 3.55, 20", rambox. It's factory stock with all updates done. I haven't gone far since the VA7, so the mileage is just off the EVIC and it's crap at 22.5US MPG or 27MPG CDN. Before I started having all these updates, last summer, when I was just driving it, my highway mileage was running at 32-35mpg CDN which is about 27mpg US. I stored it for the winter and just got it out, so now I can start seeing how the latest updates will affect it. From all indications on the EVIC, I am headed in that good mileage direction again as my cumulative mileage continues to decrease in number ... 11 - 10.9 - 10.8 - etc. I'll be doing a bit longer tomorrow, about 150km highway, so well see then.
 

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I am the second owner of a gorgeous 2016 Laramie. I bought it with just over 30,000 last August. The original owner put 20" wheels on it almost immediately after he bought it, and he never reset one of the trip meters thereafter. I'll try to post photos showing that in 39,650 miles (out of the 40,478 total on it), the truck has averaged 19.2 MPG at an average 29 MPH. The stats for the most recent 2900 miles are similar: 19.2 MPG at and average 22 MPH. So it's clear that the truck has done more city/low speed traveling than long highway, high-speed miles. The engine hours show 155 hours idling, and 1213 hours driving. Without the idle time, the math says the average speed would have been 33 MPH. The AEM recall was done on the truck just a month or two before I bought it.

I know the 20" wheels throw the mileage off by about 4%, but even adding for that it brings the average MPG to 19.968 - darn close to 20. That's a far cry from the 25, 27, or even 30 I've seen posted on this forum.

I've done very little towing with the truck in the 10,000 miles I've put on it, and I don't think the previous owner did much, if any towing. They used it as a big, comfortable commuter from their home on the beach into town for doctor's appointments and such - about an hour's drive each way on two-lane highway, probably 55 mph speeds. I take it on a 120 mile round-trip on the freeway about once a month. If I'm careful to stay at 70 mph or just under, I can eventually coax it up to 19.8, when I've started out on the trip with an average of around 17. I've never seen the meter read 20 MPG as an average, yet.

Anybody got any ideas?
I have 2016 ED... Early on, less than 5K miles we made a trip from Richmond, VA up to Cape Cod & on to Bar Harbor Me. Over the course of that trip, we averaged 27.5 mpg. This included daily trips up and down Cadillac Mtn., in Acadia National Park. Typically I was getting 22 MPG in town and 26 on trips on the freeway over an hour each way. Six months later and with no engine fault codes indicated, my milage dropped to 17 in Town and 20 HWY. I had taken it in several times complaining about what appeared to be a problem, sluggish response to throttle and milage. They did some more extensive troubleshooting and found that the Turbo had failed. There were no fault codes recorded. My milage has never recovered much since then. Following the turbo replacement, my milage came up a little 19 in Town and 23 on the hwy. I now have 34K miles on the truck. The AEM affected performance and dropped my mpg ever so slightly. I've only had one regeneration notification which happened at about 22K, though DEF is consumed. Wth MPG where it is, I'm not better off than someone driving the same truck with the Hemi.
 

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I am the second owner of a gorgeous 2016 Laramie. I bought it with just over 30,000 last August. The original owner put 20" wheels on it almost immediately after he bought it, and he never reset one of the trip meters thereafter. I'll try to post photos showing that in 39,650 miles (out of the 40,478 total on it), the truck has averaged 19.2 MPG at an average 29 MPH. The stats for the most recent 2900 miles are similar: 19.2 MPG at and average 22 MPH. So it's clear that the truck has done more city/low speed traveling than long highway, high-speed miles. The engine hours show 155 hours idling, and 1213 hours driving. Without the idle time, the math says the average speed would have been 33 MPH. The AEM recall was done on the truck just a month or two before I bought it.

I know the 20" wheels throw the mileage off by about 4%, but even adding for that it brings the average MPG to 19.968 - darn close to 20. That's a far cry from the 25, 27, or even 30 I've seen posted on this forum.

I've done very little towing with the truck in the 10,000 miles I've put on it, and I don't think the previous owner did much, if any towing. They used it as a big, comfortable commuter from their home on the beach into town for doctor's appointments and such - about an hour's drive each way on two-lane highway, probably 55 mph speeds. I take it on a 120 mile round-trip on the freeway about once a month. If I'm careful to stay at 70 mph or just under, I can eventually coax it up to 19.8, when I've started out on the trip with an average of around 17. I've never seen the meter read 20 MPG as an average, yet.

Anybody got any ideas?
1st -never ever rely on the "Lie-O'Meter" on the dash. Always hand calculate your mileage and always top your tank so you know it's close to the same level when you fill. Second, what tires (Name and model) and exact size? Then go to Discount Tire's website and look for the tires and the spec. You want to know the weight and how close they are to stock. Third, 20" tires should have been stock on a 2016 Laramie. 4th, have a dealer reset your ECU for 20" tires. 5th, unless these are oversized tires 4% is not the error. Maybe 2%. 6th, your average speeds seems to indicate a lot of low speed driving, in which case 20 mpg is about right. And, lastly, there is an update for the AEM that you should be able to get at your local dealer at now charge along with any other recall service your truck may need. Are you in FCAs system so you are getting recall notices? If not get your truck updated by the dealer.
Regarding tire weight -heavier = lower mileage. I use 275/65-20 snow tires (Cooper Discoverer) which are heavy and they cost me about 2 mpg (along with the Winter fuel mix.)
 

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Since we're on this discussion, I'm curious to know what the sweet spot RPM is for fuel mileage for the ED. In other words, on an interstate highway, where should I set my cruise control for maximum MPGs? I suggest RPM rather than speed because that should account for tire size and rear diff ratio. Hopefully I'll be able to do some open highway driving soon and when I do I'd like to see maybe 26 or 27 mpg out on the interstate.

I bought my 2016 ED just as the virus lockdown ensued and all I've done so far is local driving which is a combination of city and two-lane country roads. I haven't had an opportunity yet to drive on an interstate to evaluate it there but so far I'm reasonably happy with MPG. I've only run 1.5 tanks of fuel since I bought it in mid-February and I haven't measured it exactly but the EVIC shows between 20 and 21 when I'm making stops in town then after a couple of hours out on the two-lane it'll nudge up to 22 but then will drop back to somewhere between 20 and 21 again after a few trips in town.

For the record I really like this truck. It looks good, drives nice, smooth ride, nice interior, good stereo. I haven't experienced any of the lag or slow acceleration that some people complain about. I hope I don't jinx it but there is nothing about it that I don't like. Okay, there's maybe one tiny little nit to pick. For some reason the left side exhaust tip extends out past the bumper about an inch and a half further than the right side exhaust tip. But that's the only thing I've found so far that fails to meet expectations.
 

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in one of your pics, you have a kayak mounted, whoops, that has an affect on fuel also... you shared that the previous owner putted around and made short trips, diesels are meant to be a road warrior machine.... get the temps up on it, and run her for miles on end... and blow that EGR out... short trips to the grocery store kills these oil burners... and another thing, one way to blow her out, hook up to 5000 lbs. hit that tow haul button, and go run her for 100 mile road trip... she'll quit running likes she's got Corona virus...
 

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2019 RAM 1500 Tradesman 4X2 EcoDiesel
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GPS. Without one what you are considering is probably way off. Watch the speed on the GPS and compare that to the speedometer. Watch the odometer on the GPS and compare that to the odometer in the truck. Use the GPS readings and hand calculate to real results. If you cannot do these things you will never really know.
To check the odometer, I think it's easier to read the mileage off of the paddle markers along the highway. If you're on the same highway for 50 or 100 miles, you can get an extremely accurate calibration. The hardest thing is remembering to check after an hour or so. I assume you were referring to built-in navigation, which some of us don't have. I wouldn't be surprised if there is a phone app, though.
 

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I assume you were referring to built-in navigation, which some of us don't have.
No, he is referring to a standalone GPS unit like a Garmin or Magellan. And yes, most cellular telephones have a GPS unit and there are free apps and maps available. I use the "Avenza" app on my iPhone 6 for walking and I use a Garmin GPSmap78 for fishing and hunting.
 

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I thought we had all just accepted the fact that some of these trucks (mine included) don't get the advertised MPG. Even with GDE engine and trans tune, stock size tires, no frills, I'm still getting 21ish max MPG. Oh sure, sometimes the instant reads 27-28 for a mile or so, but I have never seen the average displayed at anywhere above 24. My hand calcs are usually at least 1mpg lower. I cruise control at 73 mph almost all the time on the freeway, and spend about half my miles on the freeway.

I wish MPG specs weren't just two numbers on a page. Or at least that they would tell you the conditions that they saw to get those two numbers. Some guy on flat ground Texas, that never sees more than 60mph is going to have different numbers than a guy driving in the Rockies with speed limits that can be as high as 80mph. Is anything wrong, or even special about either of those trucks? No. And if there is, you'll never get dealer to fully investigate it.
 
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