Regretting ordering 3.92 on my 22 Ram Ecodiesel and almost debating paying to downgrade to 3.21

[JerryETX]

Higher ratio would never be better for towing.

Lower gear ratio is better. 3:92 is a lot lower than 3:21

 

[Dr B]

MPG is all about truck aerodynamics period. Trucks have a huge drag coefficient. Anything over 60 and you will see mpg suffer.

 

[Mr John J]

California is a nice place for the weather but in some places, living shoulder to shoulder just isn't my idea of life. And the rules. regulations. loss of rights, and the number of wack-os, wow. My oldest and youngest sons both lived in California, the youngest in Riverside, and the oldest in Lake Forest. Both have left for Arizona in the past year. The cost of living and the cost of property versus the wages forced them to leave. I may have to put up with snow and cold for a few months but living rural, on 20 acres, and surrounded by the Great Lakes, I'll never leave.

I've spent my career in automotive electronics and software engineering for Ford and GM plus a handful of suppliers. My oldest stepson is also in the powertrain side of automotive and for a while, worked on the ECODiesel program at Chrysler. When I picked up my new ED, I knew the factory tune just wasn't for me so I drove over to GDE and had both the transmission tune and the engine tune installed. I put a link to what their tunes are about for the ED.

My son knew the calibration engineers at GDE, and at times, even seeming hudge, automotive can be small. These guys, all calibration engineers, know what they are doing. They have been calibrating powertrains and drivelines for years. The calibrations are outstanding while meeting emissions, returning customer satisfaction to the driving experience, increasing performance, increasing MPGs, reducing the regenerations, making good use of the low-pressure EGR, better shift logic, etc.

CARB is a pain and eventually will regulate themselves out of existence.

RAM Jeep EcoDiesel Street Legal Engine & Trans Tune - GDE

Ram Jeep EcoDiesel Compliant Engine & Trans Tune Combo. This is the only street legal RAM Jeep EcoDiesel Engine Tuning product available.

greendieselengineering.com

 

[stevedeL58]

Had to make a quick trip to Boston (MA) one night to pick up my son at the airport. Fueled the Ram up (2020 Ram 1500, Eco Diesel, 3.21 gear ratio). Took a snap shot of my dash console with the overall MPG after the trip (about 120 miles round trip from where I am located in Rhode Island). 31.3 MPG is the best I've done with average speed around 68 MPH in "moving" trafffic.

 

[David James]

Hi, I had ordered my RAM with 3.92 ratio as I only seemed to come across the good articles at that time in which I learned that it will have a higher resale value in the future, better for towing, etc. I did see some mention of a negligible difference in mpg but thought nothing of it as the sticker did not update on the MPG at all after I selected 3.92. I had even picked up the bigger diesel tank because I wanted to be able to go on long trips while dreaming about the 29mpg thats advertised lmao.

I live in California, almost everyone and their mother drives 80mph here on the highways and most drive even faster. I live in a fairly rural area, I have to drive on the highways a fair bit in order to get most things.
In my first few weeks of testing, here's what I've noticed for mpg
80mph = 2200/2250 rpm and ~20mpg
75mph = Just over 2000 rpm, maybe 2050/2075 and ~24mpg
70mph = I dont remember the exact rpm but its 27+mpg
EDIT: 70mph = a hair under 2000 rpm maybe 1950 and ~27.5 mph

I did reach out to the service department at my local dealer and was told $2,750 + labor in order to switch to a 3.21 (guy sent me a detailed parts list as for the breakdown) and I'm following up with them now to see how much labor that would be.

In terms of switching over
Pros:
For the most part I can drive as I normally do and not have to worry about being inefficient in terms of diesel
Would be saving time as well as I'd be driving at 80mph instead of 70/75

Cons:
The upfront cost of course
Potential resale value in the future may be impacted but I dont like switching cars very often
Towing impact, I dont tow much now but it was just futureproofing


You may be calling me crazy but this is bothering me so much, like how did I look into every little detail and end up making this big of a mistake. Also, I am under the assumption that going to 3.21 will give me lower RPM's at 80mph, please correct me if I'm wrong.

You will find biggest issue is aerodynamics, not gear ratio. That truck may be in it’s sweet rpm spot at 70 mph. No matter what, you won’t get mpg at 80 mph you do at 70, no matter the rear end. Save your $z. Slow down to 70. You have 5700 pounds of steel to surround you.

 

[Trashy2121]

Why not find the sweet spot in between? 3.55...

 

[Danquin1]

What about compromising and going with the 3.55. I have the 3.6 gas with 3.55 and love it. I tow 6200lb travel trailer no problem... when not towing driving at 75 I average 25/26.

 

[Wahrsuul]

Since 3.55 was not an option for the ED in the first place, would they be able to flash the system to recognize that ratio?

I have 3.55 in mine, but I've got the old 5spd. With the 8spd, it was 3.21 or 3.92 for the Hemi and ED. 3.55 was only for the V6.

 

[JohnnyMac]

MPG is all about truck aerodynamics period. Trucks have a huge drag coefficient. Anything over 60 and you will see mpg suffer.

Exactly, that's why I suggest the Cybertruck kit for the RAM.

Since 3.55 was not an option for the ED in the first place, would they be able to flash the system to recognize that ratio?

I have 3.55 in mine, but I've got the old 5spd. With the 8spd, it was 3.21 or 3.92 for the Hemi and ED. 3.55 was only for the V6.

I assume you are talking about the latest generation of EcoDiesel? My 2018 was standard with the 3:55.

 

[Docwagon1776]

I think I just puked a little.

 

[Scotty]

I have a 21 ecodiesel and almost from new it has gotten 27 to 30 at 75 to 80 all the time , pulling out of Phoenix no, in heavy winds no but under ” normal “ conditions yes all the time in town realistic numbers are 24 and yes it has 392 gears , I have a small 16 ft enclosed trailer , at 65 mph 24 25 , I really like this truck , I had a 6.7 prior and I was skeptical but the way I use this truck now works for me

 

[Retiring Don]

I purposefully bought my '19 Laramie 5.7 with 3.92 gears so I can pull my 6000+ lbs travel trailer easily through the mountains, and I average 12 mpg @ 60mph unless I'm going into head winds. Currently I have pulled over 21K miles and have 44K on the odometer. When not pulling my trailer I can get 20-21 mpg on the highway at 70 mph, and around town 16-18 unless I sit in traffic. I do know that here in Charleston, SC today I paid $3.77 for a gallon of regular and at the same station diesel was $5.41. I looked at the Eco diesel before I bought my Ram new but couldn't see any real operating cost savings. Plus I am more comfortable working on a gasoline engine than a diesel.

 

[aj_g]

I ran an 811 mile round trip in April with a combination of fwy (75mph) county rural road, city and stop and go and my total trip mpg with my 3.92 and limited slip was 33.5mpg (and verified by fuel receipts)....

Do you have GDE?

 

[aj_g]

What about compromising and going with the 3.55. I have the 3.6 gas with 3.55 and love it. I tow 6200lb travel trailer no problem... when not towing driving at 75 I average 25/26.

I wasnt given the option for 3.55 when buying, just 3.21 or 3.92, hence I thought 3.21 was the only option

 

[Wahrsuul]

When last I looked, 3.55 and 3.21 were the options for the V6, 3.21 and 3.92 for the Hemi and ED. But that was a year or so ago when I was thinking about ordering a new truck.

I'd love to have one of the Aero Caps, but the only ones I've seen for the fourth gen Rams are either home made or on Alibaba. There's a company that makes one for the fifth gen trucks I believe.

 

[2020PW]

How do the tunes work with the emissions? There’s some great articles about how tunes create get power and MPG but also a lot of soot and destroy the emission filter.

Does the transmission hold up to the additional power? 66rfe won’t with a ****** without a 8k rebuild.

OP, change your tire size as the is change the gear ratio. Or just slow down.

 

[SouthernBornRebel]

Being born in California and leaving was best choice we made... Y'all's answers are all cured at Voting Booth....js

 

[SouthernBornRebel]

It'd be worth paying to Upgrade to 3.92's over paying to Downgrade to 3.21's... at Hwy speeds you won't see much difference in MPGs...
Here's a good ref: https://www.dodge-forum.eu/index.ph...-s-ultimate-guide-to-3-21-vs-3-92-axle-ratio/

 

[farout75]

Hi, I had ordered my RAM with 3.92 ratio as I only seemed to come across the good articles at that time in which I learned that it will have a higher resale value in the future, better for towing, etc. I did see some mention of a negligible difference in mpg but thought nothing of it as the sticker did not update on the MPG at all after I selected 3.92. I had even picked up the bigger diesel tank because I wanted to be able to go on long trips while dreaming about the 29mpg thats advertised lmao.

I live in California, almost everyone and their mother drives 80mph here on the highways and most drive even faster. I live in a fairly rural area, I have to drive on the highways a fair bit in order to get most things.
In my first few weeks of testing, here's what I've noticed for mpg
80mph = 2200/2250 rpm and ~20mpg
75mph = Just over 2000 rpm, maybe 2050/2075 and ~24mpg
70mph = I dont remember the exact rpm but its 27+mpg
EDIT: 70mph = a hair under 2000 rpm maybe 1950 and ~27.5 mph

I did reach out to the service department at my local dealer and was told $2,750 + labor in order to switch to a 3.21 (guy sent me a detailed parts list as for the breakdown) and I'm following up with them now to see how much labor that would be.

In terms of switching over
Pros:
For the most part I can drive as I normally do and not have to worry about being inefficient in terms of diesel
Would be saving time as well as I'd be driving at 80mph instead of 70/75

Cons:
The upfront cost of course
Potential resale value in the future may be impacted but I dont like switching cars very often
Towing impact, I dont tow much now but it was just futureproofing


You may be calling me crazy but this is bothering me so much, like how did I look into every little detail and end up making this big of a mistake. Also, I am under the assumption that going to 3.21 will give me lower RPM's at 80mph, please correct me if I'm wrong.

The diesel in the 1500 is a "light duty diesel" and it does it's best for fuel mileage. but towing, a 5.7 actually tows more weight and costs 4 grand less. The V. M. Morori diesel, which in made in Italy has had its problems in the last two generations before the newest one. I would not change gear ratio's as its at least $2,500. and you will never recover the cost to change out the gears ratio. For what you paid for the 1500 you almost could have got a RAM 2500 with a Cummings diesel. I would just enjoy what you have and keep trucking. Keep up the filter changes that is critical. I had a V. M. Motorie diesel and RAM brought it back because in 16 months it was in the shop 25 times. I want no more Italian engines personally.

 

[06 Dodge]

The diesel in the 1500 is a "light duty diesel" and it does it's best for fuel mileage. but towing, a 5.7 actually tows more weight and costs 4 grand less. The V. M. Morori diesel, which in made in Italy has had its problems in the last two generations before the newest one. I would not change gear ratio's as its at least $2,500. and you will never recover the cost to change out the gears ratio. For what you paid for the 1500 you almost could have got a RAM 2500 with a Cummings diesel. I would just enjoy what you have and keep trucking. Keep up the filter changes that is critical. I had a V. M. Motorie diesel and RAM brought it back because in 16 months it was in the shop 25 times. I want no more Italian engines personally.

I looked at a eco diesels before I bought my 2500 CTD, I was surprised that the MSRP on it was higher then the truck I bought....