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MPG effect of 3.92 rear end

Horkn

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I didn't say it would NEVER downshift. I just meant a 3.92 would downshift LESS with small inclines and hills.


I just re read your post about his truck, and I still see it that his 3.92 equipped truck is downshifting as you suggested it shouldn't be.

I'll let it go;)
 
U

User_3336

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what ever you say...

Have you ever owned a ram 1500 hemi with the 3.21 and another with the 3.92 and experienced the difference?

**** me! LOL

I just re read your post about his truck, and I still see it that his 3.92 equipped truck is downshifting as you suggested it shouldn't be.

I'll let it go;)
 

Horkn

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what ever you say...

Have you ever owned a ram 1500 hemi with the 3.21 and another with the 3.92 and experienced the difference?

**** me! LOL

No I've not owned any ram. But that fact has nothing to do with what I've pointed out.

I was just reading what you wrote, after not reading what the guy that you quoted, wrote. Lol

Getting back to the point of this thread, I have no reason to believe what others that own a 3.21 geared new ram are saying.
I have the 3.92. At 4 lanes highway speeds, it's more than 1 mpg. More like 2-3 mpg difference. MPG goes down rapidly over 2000 RPM.


And..
I have had 4 Ram's now with every gear ratio. I was going to build a truck and opt for 3.92. I found a truck on the lot that someone had ordered with every option except bed liner and I had the dealer do a linex. My new truck has 3.21 and to be honest I am very happy. The 3.21 actually suits my needs very well as I travel on the highway a lot. I seldom tow and the Hemi has plenty of power, I just came from and eco diesel. At 51 years of age I could care less how fast a 3.92 gets off the line or performs, I'll take the mpg all day and everyday. I believe the 3.21 gives you more then 2mpg over the 3.92. Get what you like it's your money and everyone uses their trucks differently. Mine is a big family vehicle.

Then there's the etorque pcm and the other reflashes which hopefully help mpg. I've been doing a lot of research and reading on these trucks. I really liked the 2019 etorque hemi rebel I drive, but the mpg they've been reporting is worse than what my Audi wagon gets. While that shouldn't sounds too difficult to achieve, my Audi sucks gas as it's a 4.2 v8. It's got 3.90 geared with front and rear electronically locking differentials, but only a 5 spd. So I see the same issue that ram owners with 3.92's are seeing on the freeway. My Audi gets the best mpg at 55-60 mph ( about 20 mpg at like 2000 rpm) Bump that to 70mph, and the mpg goes down considerably. At sustained 75 mph ( 2900 rpm) it gets 18 mpg at best, and that's with the air suspension at level 1. Audi thought that the 2 speed transfer case that the rest of the world got wasn't needed in North America, so they just put high numerical axles in it. :(

Our 3.73 geared v8 4runner, again with a 5spd auto, does 75 mph at 2200 and gets better mpg than my Audi at freeway speeds. That 2 speed transfer case really helps because a higher profile, and heavier vehicle getting that mpg it's pretty good, even with only a 5spd auto.

I think a 3.21 geared etorque hemi crew would work well for me. I also know a similarly geared 5.0 supercrew would do well for me. Either truck would work better for me for what I need it for, than my Audi.
 

mhb1638

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Are you not taking a bath on depreciation of the trade-in vehicle? Even if the new one averages 20mpg, it will take you 10 years (and 380k miles) to recoup even $5750. That's driving 104 miles for 365 days a year. If you are only making the drive 5 days a week for work, the savings drop to $4100. Doesn't seem worth it to me, unless you are getting a smoking deal.
I got 1k in equity which may not seem much but its not negative either. I didn't get a smoking deal, but I did get "a" deal. I picked up a fully loaded 4x2 Limited tonight which every bell and whistle there is, minus 3.92 :). Sticker was 61k got it for 53k.
 

mxracer32

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With your high use of interstate highways and concern for mpg, I'd get the 3.21. The 3.92 takes a nose dive on economy above 65 mph.

makes sense then- here in Charlotte and surrounding areas the interstates speed limits are between 60mph and 70mph, which means we all do 80mph...
 
U

User_3336

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Now, the TREMOR, that was one fun truck to drive. That 4.10 axle ratio was awesome!!! Of course, it was paired with the 6-speed Ecoboost, but that truck could climb hills and tow effortlessly!! Only a one year run though. tremor.jpg


So before I had this Rebel I had a FX2 F150 Tremor
View attachment 10035

2 door truck, 3.5 1st Gen EcoBoost with a 4.10 rear end, it was a fun truck, this was my average MPG at well you can see


That truck hovered between 16.8 and 15.9 depending on if I was in a headwind and doing 80,.
 
U

User_3336

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UMMMM. Not slamming and not hassling. Anyone debating the difference between a 3.21 and a 3.92 should drive BOTH themselves and judge both, and choose the truck that suits their needs, not necessarily what others say on message boards. Everyone has different driving styles, so what one may experience between the two gearing ratios may be totally different.

What I said in my posts are my opinions and MY experiences.
-----------------------------------------------------------------------------------
I seen ALOT of gear hunting with the 3.21 (between 6-7-8) (MY EXPERIENCE)

With a 3.21 sounds pretty typical. If you had the 3.55 or the 3.92, you would definitely not see this downshifting to 7th (or possibly 6th) in the scenario you posted. (POSSIBLE DRIVING STYLES)

You will reget getting a 3.21 axle ratio after owning a 3.92 one! (OPINION - i've owed BOTH)

I didn't say it would NEVER downshift. I just meant a 3.92 would downshift LESS with small inclines and hills.
(different driving styles - conservative vs aggressive?????)
-------------------------------------------------------------------------------------

No sense to keep quoting my posts if you are just going to disagree with them.

ExcursionDiesel, your point?

Horkn, perhaps you should just go drive both and judge for yourself, or you even interested in buying a RAM?



Ya know, I came here before I owned a Ram. I had enough sense to read and decide what options fit my needs. Let's give the guy your slamming the benefit of the doubt. No reason to hassle him. This isn't a contest.
 

mhb1638

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UMMMM. Not slamming and not hassling. Anyone debating the difference between a 3.21 and a 3.92 should drive BOTH themselves and judge both, and choose the truck that suits their needs, not necessarily what others say on message boards. Everyone has different driving styles, so what one may experience between the two gearing ratios may be totally different.

What I said in my posts are my opinions and MY experiences.
-----------------------------------------------------------------------------------
I seen ALOT of gear hunting with the 3.21 (between 6-7-8) (MY EXPERIENCE)

With a 3.21 sounds pretty typical. If you had the 3.55 or the 3.92, you would definitely not see this downshifting to 7th (or possibly 6th) in the scenario you posted. (POSSIBLE DRIVING STYLES)

You will reget getting a 3.21 axle ratio after owning a 3.92 one! (OPINION - i've owed BOTH)

I didn't say it would NEVER downshift. I just meant a 3.92 would downshift LESS with small inclines and hills.
(different driving styles - conservative vs aggressive?????)
-------------------------------------------------------------------------------------

No sense to keep quoting my posts if you are just going to disagree with them.

ExcursionDiesel, your point?

Horkn, perhaps you should just go drive both and judge for yourself, or you even interested in buying a RAM?

I see your experience and raise you...I've owned a 15 3.21, 16 3.92. 17 rebel, now 19 3.92. I've owned them all and while the 3.92 is great off the line, it has no problem ssucking gas on the highway. 3.21 gears will easily net 20mpg.
 
U

User_3336

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the 3.92 will easily run 2000 RPM(or more) on the interstate, but I managed to average 18mph combined on a 3.92 Quad Cab Night Sport.
In MY opinion, I still think the 3.92 is the best OVERALL LONG TERM decision. I didn't let 2mpg skew my decision in that truck.

I see your experience and raise you...I've owned a 15 3.21, 16 3.92. 17 rebel, now 19 3.92. I've owned them all and while the 3.92 is great off the line, it has no problem ssucking gas on the highway. 3.21 gears will easily net 20mpg.
 

Horkn

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There ya go. You DO NOT own a RAM. So no real world experience, eh?
Ya know, I came here before I owned a Ram. I had enough sense to read and decide what options fit my needs. Let's give the guy your slamming the benefit of the doubt. No reason to hassle him. This isn't a contest.
UMMMM. Not slamming and not hassling. Anyone debating the difference between a 3.21 and a 3.92 should drive BOTH themselves and judge both, and choose the truck that suits their needs, not necessarily what others say on message boards. Everyone has different driving styles, so what one may experience between the two gearing ratios may be totally different.

What I said in my posts are my opinions and MY experiences.
-----------------------------------------------------------------------------------
I seen ALOT of gear hunting with the 3.21 (between 6-7-8) (MY EXPERIENCE)

With a 3.21 sounds pretty typical. If you had the 3.55 or the 3.92, you would definitely not see this downshifting to 7th (or possibly 6th) in the scenario you posted. (POSSIBLE DRIVING STYLES)

You will reget getting a 3.21 axle ratio after owning a 3.92 one! (OPINION - i've owed BOTH)

I didn't say it would NEVER downshift. I just meant a 3.92 would downshift LESS with small inclines and hills.
(different driving styles - conservative vs aggressive?????)
-------------------------------------------------------------------------------------

No sense to keep quoting my posts if you are just going to disagree with them.

ExcursionDiesel, your point?

Horkn, perhaps you should just go drive both and judge for yourself, or you even interested in buying a RAM?


Well, go back to your quote where you mentioned that if the other poster would have had 3.92 gears, that he wouldn't be going out of 8th gear in the situations he was describing. Then go back and look at that posters sig line and you'd see he in fact dues have the 3.92 gears. That's where I went. Then you had to go where you went, and now you should see why you are getting flack.

The ram is not unlike any other vehicle, in that a higher numerical axle ratio will probably get lower mpg at the same freeway speeds as the same model with lower numerical gears. That's just simply how it works.

While I don't own a 19 ram, I'm being an informed prospective buyer by researching on this forum based on people's experience. ;)

When I hear that the 3.21 geared 19 rams do get much better freeway mileage than the 3.92 geared ones, then it does pique my interest. Since I've driven the rebel with 3.92's and the taller duratracs, I will go and test a 3.21 equipped 19 hemi ram with the off road package.
 

Creep0321

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Well, go back to your quote where you mentioned that if the other poster would have had 3.92 gears, that he wouldn't be going out of 8th gear in the situations he was describing. Then go back and look at that posters sig line and you'd see he in fact dues have the 3.92 gears. That's where I went. Then you had to go where you went, and now you should see why you are getting flack.

The ram is not unlike any other vehicle, in that a higher numerical axle ratio will probably get lower mpg at the same freeway speeds as the same model with lower numerical gears. That's just simply how it works.

While I don't own a 19 ram, I'm being an informed prospective buyer by researching on this forum based on people's experience. ;)

When I hear that the 3.21 geared 19 rams do get much better freeway mileage than the 3.92 geared ones, then it does pique my interest. Since I've driven the rebel with 3.92's and the taller duratracs, I will go and test a 3.21 equipped 19 hemi ram with the off road package.
Did you test that ORP 3.21 truck?
 

Hammer1

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UMMMM. Not slamming and not hassling. Anyone debating the difference between a 3.21 and a 3.92 should drive BOTH themselves and judge both, and choose the truck that suits their needs, not necessarily what others say on message boards. Everyone has different driving styles, so what one may experience between the two gearing ratios may be totally different.

What I said in my posts are my opinions and MY experiences.
-----------------------------------------------------------------------------------
I seen ALOT of gear hunting with the 3.21 (between 6-7-8) (MY EXPERIENCE)

With a 3.21 sounds pretty typical. If you had the 3.55 or the 3.92, you would definitely not see this downshifting to 7th (or possibly 6th) in the scenario you posted. (POSSIBLE DRIVING STYLES)

You will reget getting a 3.21 axle ratio after owning a 3.92 one! (OPINION - i've owed BOTH)

I didn't say it would NEVER downshift. I just meant a 3.92 would downshift LESS with small inclines and hills.
(different driving styles - conservative vs aggressive?????)
-------------------------------------------------------------------------------------

No sense to keep quoting my posts if you are just going to disagree with them.

ExcursionDiesel, your point?

Horkn, perhaps you should just go drive both and judge for yourself, or you even interested in buying a RAM?
I have had all 3 gear ratios and I don't regret the 3.21 one bit. If I ordered a truck I would have went with 3.92 and it would have been a mistake considering the driving that I do.
 

Troop2865

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OK. I have about 1300 mile on my truck so I know it is not fully broke in. I just filled after a little over 250 miles. 80 percent was driving interstate (65 and 70 MPH). I drove the speed limit There was a headwind going south and a good tailwind going north. I live in the country, so most of the other driving is 55 MPH going to and from town, with a little in town driving. I really babied it this tank (really, I baby it every tank). I have also been filling with Shell, although only 87 octane.

When I filled this morning I averaged 13.37. The computer showed 13.4. After I filled, I checked the computer instant mileage at different speeds (I have done this many times). Here are my best observed MPG at stated speeds:

45 MPH - 18 MPG
50 MPH - 18 MPG
55 MPH - 16 MPG

Driving 70 on the interstate last trip, it would bump 15 going on a slight downhill, but showed 13 the majority of the time. This was with a tailwind.

While I know many are tired of hearing MPG complaints, I am really wondering if others have experienced mileage this far off EPA estimates. I know Ram should not have bunched all of the Hemi trucks in the in the same category. I know mine has 3.92's and the Off Road Group. I know mine has 35 inch tires now, but it really wasn't much, if any better with the factory tires.

I saw an old post where there were two people with Rebels posting to Fuelly and they were averaging less than 13. I guess mine is equipped like a Rebel so I should expect no difference, but I really expected to get 17-18 running the speed limit on the interstate, not 13.

Have any others experienced the same poor mileage driving easy? More importantly, was there a mechanical issue causing poor mileage?

Love the truck. The fuel economy......not so much.
 

GRAYWOLF

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I just traded my 2012 300S with 3.91 and averaged 13.5 MPG over 2 years and more than 19K miles.
I just filled my tank for the first time in the truck (3.21) and averaged 11.7 (about what I got most of the time in the car commuting to work).

Granted, one tank does not tell the full story and they are different vehicles, but so far, I am not seeing any real difference in mileage, so far. I am curious to see what I end up getting on the highway.
 

ExcursionDiesel

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OK. I have about 1300 mile on my truck so I know it is not fully broke in. I just filled after a little over 250 miles. 80 percent was driving interstate (65 and 70 MPH). I drove the speed limit There was a headwind going south and a good tailwind going north. I live in the country, so most of the other driving is 55 MPH going to and from town, with a little in town driving. I really babied it this tank (really, I baby it every tank). I have also been filling with Shell, although only 87 octane.

When I filled this morning I averaged 13.37. The computer showed 13.4. After I filled, I checked the computer instant mileage at different speeds (I have done this many times). Here are my best observed MPG at stated speeds:

45 MPH - 18 MPG
50 MPH - 18 MPG
55 MPH - 16 MPG

Driving 70 on the interstate last trip, it would bump 15 going on a slight downhill, but showed 13 the majority of the time. This was with a tailwind.

While I know many are tired of hearing MPG complaints, I am really wondering if others have experienced mileage this far off EPA estimates. I know Ram should not have bunched all of the Hemi trucks in the in the same category. I know mine has 3.92's and the Off Road Group. I know mine has 35 inch tires now, but it really wasn't much, if any better with the factory tires.

I saw an old post where there were two people with Rebels posting to Fuelly and they were averaging less than 13. I guess mine is equipped like a Rebel so I should expect no difference, but I really expected to get 17-18 running the speed limit on the interstate, not 13.

Have any others experienced the same poor mileage driving easy? More importantly, was there a mechanical issue causing poor mileage?

Love the truck. The fuel economy......not so much.
My truck is a 3.92 with Off Road Group. The only difference is you have a 2.5 lift and bigger tires. Your steady speed instantaneous mpg are 2-3 mpg less than what I'm seeing. Not sure how much a lift and bigger tires cost in economy but 2-3 mpg seems about right.

Are you running max psi on your tires? Lower pressure on big tires creates a lot of rolling resistance.
 

SpeedyV

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My truck is a 3.92 with Off Road Group. The only difference is you have a 2.5 lift and bigger tires. Your steady speed instantaneous mpg are 2-3 mpg less than what I'm seeing. Not sure how much a lift and bigger tires cost in economy but 2-3 mpg seems about right.

Are you running max psi on your tires? Lower pressure on big tires creates a lot of rolling resistance.
Yeah, @GRAYWOLF has got to be paying for that lift in mileage at higher speeds. Mine's a heavily-optioned truck with 3.92 and ORG, and I'm probably seeing similar economy (18 or slightly better) at 45-50. The difference is that mine doesn't drop off as fast at higher speeds. I will see at least 15 mpg at 75 mph. Right now, I'm on a worst-case "city only" tank with a lot of idling and stop-and-go, and I'm seeing 13s.
 

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