3.92 with the Ecodiesel

[Neurobit]

Oh, and I believe Ford’s new PowerBoost is rated at 24MPG combined, but I think on those you can the get 3.55 gearing so that would make a difference also. Even the 3.73 would help I’d imagine.

 

[IvoryHemi]

Just an FYI the gear ratios that were posted in that chart are no longer accurate either.... We have minor gear ratio changes with the new 8HP75 transmission
4thGen / 5th Gen
8HP70 / 8HP75
First – 4.71/ 5.00
Second – 3.14/ 3.20
Third – 2.10/ 2.14
Fourth – 1.66/ 1.72
Fifth – 1.28/ 1.31
Sixth – 1.00/ 1.00
Seventh – 0.83/ 0.82
Eighth – 0.66/ 0.64
Reverse – 3.30/ 3.45

That’s incorrect. While ZF offers that set of gear ratios with 5.0 first gear, FCA doesn’t use it.

FCA only uses the 4.71/3.14/2.10/1.67/1.29/1.00/0.84/0.67 gear set

 

[Rebelguy2020]

I ordered my 10th edition limited long horn 3.92 gears eco diesel. My second one, love these engines! Won't be here till March 2021 I have. 2014 ecodiesel ram long horn with 3.55 and it fine too, get 22 mileage per gallon all around driving, before recall got 25 miles per. And tows good, but half the fuel milage, which is good for towing. My friend has a 2016 eco diesel with 3.92 and love it's. say it's worth the less fuel miliage. I hope this new motor wholes up like last one? My EGR is still good on 2014, but there is a recall on it. It has 140,000 miles on it.

You will love your truck with the new diesel, my Rebel diesel is awesome, it only comes with the 3.92 and it is a good combination, it does rev more on highway speed, in my case here in Northern Ontario the speed limit is 90 kph or 55 mph and I usually go 100 kph or 60 mph @ 1750 rpm.
As for fuel efficiency, it is by far way better than my previous 2011 Hemi 5.7 Outdoorsman also with the 3.92, I did like my older truck but I hated having to gas it up.

 

[J-Cooz]

I so very much regret not reading this forum until after my purchase. Last week, I purchased a 2021 Laramie Longhorn with the 3.0 EcoDiesel and 3.92 gearing. My trade in was a 2019 Ford F150 with the 3.0 PowerStroke V6. In my side job, I normally transport 20 bumper pull travel trailers annually, weighing between 5000-9000 pounds. My biggest complaint is HIGHWAY MILEAGE! I drive normally 80 with the cruise on going to pick up these trailers empty and averaged 25-27mpg with my Ford. Driving home the best I can get with the Ram is 21-22mpg. This figure alone has already got me looking to see when I can get out of the truck without loosing way too much money. Yes, I am quietly kicking myself for not reading about the difference of the 3.21 vs 3.92.

Try slowing down a notch? I don't think the 3.21 would make a huge difrence at those speeds. I can get 28-30 at 72mph in my 3.92 Ecodiesel no problem. Don't forget your truck isn't broken in yet and with cold temperatures you'll get worse mileage.

 

[tom318]

That does seam pretty low. I have noticed the fuel economy is very sensitive, a slight wind or rain and any chance for decent mpg is history. I rarely do 80 but often set Cruise to 72-75 and unloaded with me alone I’ll see 28-30mpg. I once had 500lbs in the bed (2 Honda trx90 Atvs) and on the same trip averaged 23 instead of 28-30. Also lots of rain on that trip. My buddy has the 3.0 power stroke, XLT crew cab, long bed with 3.55 I think and overall my ram does better by 3-4mpg in most cases. Towing 2 atvs he would get 16-17, mine with the same load did 18-20.

 

[jdefoe0424]

I so very much regret not reading this forum until after my purchase. Last week, I purchased a 2021 Laramie Longhorn with the 3.0 EcoDiesel and 3.92 gearing. My trade in was a 2019 Ford F150 with the 3.0 PowerStroke V6. In my side job, I normally transport 20 bumper pull travel trailers annually, weighing between 5000-9000 pounds. My biggest complaint is HIGHWAY MILEAGE! I drive normally 80 with the cruise on going to pick up these trailers empty and averaged 25-27mpg with my Ford. Driving home the best I can get with the Ram is 21-22mpg. This figure alone has already got me looking to see when I can get out of the truck without loosing way too much money. Yes, I am quietly kicking myself for not reading about the difference of the 3.21 vs 3.92.

I think that there's a lot here that is left unsaid.
What trim was your F150? What gearing was it equipped with? Did it have a tonneau cover? Did it have running boards?

And for your Ram. First, you did buy almost the heaviest trim level.
It comes standard with running boards I believe. I'm pretty sure that the running boards I added to my truck hurt my mileage.
Does it have the ORG or another package that adds the AT tires?
Lastly, don't believe the EPA estimate on the sticker for these rams...they are only correct for a tradesman truck with the same cab, bed, gearing and engine. It's especially true when you're looking at a Longhorn or Limited which can be quite a bit heavier depending on options, the Rebel trim is another where there is a large discrepancy because of the factory lift and off-road tires.

Another comment, I find the cruise control on the Rams to be quite aggressive. I find that my truck may downshift to maintain speed up a small hill, whereas if I control it with my foot it would not change gears. You might get better mileage controlling speed with your foot.

Beyond all that, how do you like the interior of your Ram compared to the Ford you had?

 

[Roaminglost]

I think that there's a lot here that is left unsaid.
What trim was your F150? What gearing was it equipped with? Did it have a tonneau cover? Did it have running boards?

And for your Ram. First, you did buy almost the heaviest trim level.
It comes standard with running boards I believe. I'm pretty sure that the running boards I added to my truck hurt my mileage.
Does it have the ORG or another package that adds the AT tires?
Lastly, don't believe the EPA estimate on the sticker for these rams...they are only correct for a tradesman truck with the same cab, bed, gearing and engine. It's especially true when you're looking at a Longhorn or Limited which can be quite a bit heavier depending on options, the Rebel trim is another where there is a large discrepancy because of the factory lift and off-road tires.

Another comment, I find the cruise control on the Rams to be quite aggressive. I find that my truck may downshift to maintain speed up a small hill, whereas if I control it with my foot it would not change gears. You might get better mileage controlling speed with your foot.

Beyond all that, how do you like the interior of your Ram compared to the Ford you had?

agree with you on cruise its pretty aggressive

 

[WXman]

I so very much regret not reading this forum until after my purchase. Last week, I purchased a 2021 Laramie Longhorn with the 3.0 EcoDiesel and 3.92 gearing. My trade in was a 2019 Ford F150 with the 3.0 PowerStroke V6. In my side job, I normally transport 20 bumper pull travel trailers annually, weighing between 5000-9000 pounds. My biggest complaint is HIGHWAY MILEAGE! I drive normally 80 with the cruise on going to pick up these trailers empty and averaged 25-27mpg with my Ford. Driving home the best I can get with the Ram is 21-22mpg. This figure alone has already got me looking to see when I can get out of the truck without loosing way too much money. Yes, I am quietly kicking myself for not reading about the difference of the 3.21 vs 3.92.

371,000 combined miles now from real owners on Fuelly.com and the 3rd Gen EcoDiesel is averaging 22 MPG.

My personal truck is seeing 21 MPG on most tanks where I'm not towing.

 

[Finn5033]

I had a 2019 with the hemi and 3.21 gears. I would average about 19-19.5 mpg on my daily 80 mile work commute, and 8.5mpg pulling my 5k lb RV fish house.
Now with my 2020 ecodiesel with 3.92 gears I get 26.5-27mpg on the same work commute and average 13-14mpg pulling the same camper.

 

[Uga40]

i have 3.92 gears, 2020, BH, average 24 city 28 hwy and 14 MPG pulling 6300K LB Travel Trailer

 

[Dadeoo]

WXman, you keep posting this same misinformation.

eads, and it's wrong in this thread. Read this chart, look at the numbers, and please stop posting bad data. You're confusing other people as well and possibly causing them to purchase the wrong gear (costing them mpg).

The shaded cells are where the 3.21 and 3.92 are pretty much equal, just offset by 1 gear. You can see the difference is minimal.

You only benefit from the 3.92 if you're pulling a very heavy load (to get off the line; while towing at city or highway speeds, both will have the same final ratio available, just offset by a gear). Or, if you plan on offroading like the rebel, where the 3.92's extra torque in first is a benefit for rock crawling.

View attachment 53435

Pretty much equal is not =
I side with WX.
Your difference table proves his point. At no place are the

WXman, you keep posting this same misinformation. It's wrong in the other threads, and it's wrong in this thread. Read this chart, look at the numbers, and please stop posting bad data. You're confusing other people as well and possibly causing them to purchase the wrong gear (costing them mpg).

The shaded cells are where the 3.21 and 3.92 are pretty much equal, just offset by 1 gear. You can see the difference is minimal.

You only benefit from the 3.92 if you're pulling a very heavy load (to get off the line; while towing at city or highway speeds, both will have the same final ratio available, just off by a gear). Or, if you plan on offroading like the rebel, where the 3.92's extra torque in first is a benefit for rock crawling.

View attachment 53435

Your table proves WX right. None of the ratios are equal. Nearly = is not =. Plus, at normal egal top speeds the 3.92 gearing is going to use that 8th gear much more, while the 3.21 will drop down to 7th unless going on flats with very lite touch.

 

[VernDiesel]

Take 1st gear out of the equation. Both trucks Accelerating with a heavy travel trailer with say 50 percent throttle from say 10 mph in 2nd gear to 65 mph. The 3.92 will still do it quicker and more easily than the 3.21.

Why because even if the final drive ratios had ended up being exactly the same you are dividing the work over 5 gears with the 3.92 instead of 4 gears with the 3.21. The extra split second on one extra gear change will not make up the difference. Dividing the work by 5 instead of four makes it easier for the engine to do which allows it to do it at a greater rate of acceleration.

 

[VernDiesel]

BTW like mghurle I to transport TTs with my 3.92 ED and in the well 4 to 9k range. Only mine is with a 4th gen. Oddly mine seems to do better on fuel than his even when towing boxy TTs. However mine does benefit from GDE engine & trans tunes. Also it benefits considerably with how much better it can tow with GDE’s cruise control settings. Lastly that’s generally towing mostly at 65/66 mph. He may be towing at higher speeds which require more fuel.

When running with no TT at 80 mph or running local only I average 22.5/23 mpg. BTW the ole girl just turned 750,000 miles. Also great motor for towing assuming you’re sticking to 1/2 ton appropriate loads (say to 8k TT) and towing to 65 mph. If you need to tow heavier and faster than that the Cummins / HD is a better tool for the job. In fact with the heavier loads & higher speeds the EDs fuel savings over the Cummins disappears.

 

[silver billet]

Pretty much equal is not =
I side with WX.
Your difference table proves his point. At no place are the

Your table proves WX right. None of the ratios are equal. Nearly = is not =. Plus, at normal egal top speeds the 3.92 gearing is going to use that 8th gear much more, while the 3.21 will drop down to 7th unless going on flats with very lite touch.

No, don't get stuck on a technicality. The difference is insignificant, which is the point.

 

[bill-e]

Love my 3.92 performance and mileage. A little better than my Gen 2 in mpg and a lot better in performance.

 

[Pristine1]

Depends on how much you want to tow. The 4x4 crew I just ordered was only good to tow just over 8k with the 3.21. Going to the 3.92 put it to 9,800. From an engineering stand point the 3.92 still has the mechanical advantage gear for gear over the 3.21. The chart clearly shows this and the tow ratings reflect this. If you’re only worried about fuel mileage then absolutely get the 3.21. If you’re not going to do larger tires, probably 3.21. If you plan to tow decent sized travel trailers through the mountains... probably 3.92. If you want the fastest eco diesel by a nose to the next red light then probably 3.92.

 

[silver billet]

Tow ratings are gimped, just like EPA mpg numbers are.

With our 8 speeds, in the real world, you won't see much difference towing between a 3.21 and a 3.92, sorry. Just the first and second gear. Take it a little bit slower off the line with the 3.21. These trucks are not that well equipped to handle over 8000 pounds; the suspension is squirrely, the payload is too little, and the truck is not heavy enough to control the tail.

 

[Finn5033]

Tow ratings are gimped, just like EPA mpg numbers are.

With our 8 speeds, in the real world, you won't see much difference towing between a 3.21 and a 3.92, sorry. Just the first and second gear. Take it a little bit slower off the line with the 3.21. These trucks are not that well equipped to handle over 8000 pounds; the suspension is squirrely, the payload is too little, and the truck is not heavy enough to control the tail.

Exactly, people are always mentioning their tow rating which doesn’t matter. You’ll run out of payload before you can ever tow 10k lbs

 

[Willwork4truck]

I so very much regret not reading this forum until after my purchase. Last week, I purchased a 2021 Laramie Longhorn with the 3.0 EcoDiesel and 3.92 gearing. My trade in was a 2019 Ford F150 with the 3.0 PowerStroke V6. In my side job, I normally transport 20 bumper pull travel trailers annually, weighing between 5000-9000 pounds. My biggest complaint is HIGHWAY MILEAGE! I drive normally 80 with the cruise on going to pick up these trailers empty and averaged 25-27mpg with my Ford. Driving home the best I can get with the Ram is 21-22mpg. This figure alone has already got me looking to see when I can get out of the truck without loosing way too much money. Yes, I am quietly kicking myself for not reading about the difference of the 3.21 vs 3.92.

Guess I’d just slow down a bit, but thats me. Still sounds like a nice truck you have.

 

[Willwork4truck]

I think that there's a lot here that is left unsaid.
What trim was your F150? What gearing was it equipped with? Did it have a tonneau cover? Did it have running boards?

And for your Ram. First, you did buy almost the heaviest trim level.
It comes standard with running boards I believe. I'm pretty sure that the running boards I added to my truck hurt my mileage.
Does it have the ORG or another package that adds the AT tires?
Lastly, don't believe the EPA estimate on the sticker for these rams...they are only correct for a tradesman truck with the same cab, bed, gearing and engine. It's especially true when you're looking at a Longhorn or Limited which can be quite a bit heavier depending on options, the Rebel trim is another where there is a large discrepancy because of the factory lift and off-road tires.

Another comment, I find the cruise control on the Rams to be quite aggressive. I find that my truck may downshift to maintain speed up a small hill, whereas if I control it with my foot it would not change gears. You might get better mileage controlling speed with your foot.

Beyond all that, how do you like the interior of your Ram compared to the Ford you had?

All very good points. I was too lazy to ask many of the same, especially trim level. A Ford XLT has nothing to compare with a Longhorn... just sayin’ as I had an XLT and they are/were p l a i n...