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Bad fuel mileage 5.7 hemi

I guess those of us with 3.92s have to run 60mph everywhere to get good mpg.. I think manufacturers need to consider that most interstates are 70 mph now and try to target the optimal OD ratio for 70-75 mph.
I'm no engineer, but seems like a reasonable concept.
 
I guess those of us with 3.92s have to run 60mph everywhere to get good mpg.. I think manufacturers need to consider that most interstates are 70 mph now and try to target the optimal OD ratio for 70-75 mph.
I'm no engineer, but seems like a reasonable concept.
Your point is totally valid, but manufacturers (only) focus on achieving the best possible scores on EPA tests. I can’t fault them for this; they have to meet federal requirements, and (until buyers stop purchasing their products) they have little motivation to focus on anything else. For us to see real-world improvements, we’d need the EPA to update their tests (again) to better reflect actual conditions.
 
I guess those of us with 3.92s have to run 60mph everywhere to get good mpg.. I think manufacturers need to consider that most interstates are 70 mph now and try to target the optimal OD ratio for 70-75 mph.
I'm no engineer, but seems like a reasonable concept.

Well, they made the 3.21 for that.


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I guess those of us with 3.92s have to run 60mph everywhere to get good mpg.. I think manufacturers need to consider that most interstates are 70 mph now and try to target the optimal OD ratio for 70-75 mph.
I'm no engineer, but seems like a reasonable concept.

Valid but I know in my case I just go with the flow of traffic, I don’t try to go slow to improve my MPG. I wish it would stay up when above 70 fortunately 70 is about the max I can go on my commute. Did a FL to MN trip I was 15 or above the whole 1200 miles. Never higher than 19 though.


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I found when I'm driving on flat highway without a head wind I get 19-20 mpg going 78 mph.
 
Yes, you are correct. I have yet to do a road trip long enough to go through a full tank. My longest trip was up to the mountains and back with an average speed of 70 mph. I went through 3/4 of a tank and the rest was city driving before I filled up. I got 19 mpg average on that tank hand calculated.
 
Hey guys, quick question. This is my first 5.7 Hemi (just traded my EcoDiesel for a 2019 Ram Rebel) and I've got around 1,100km (683 Miles) and I have an economy of 18L/100km (13 MPG). I don't expect a diesel-like fuel economy but the window sticker claims it can do 13.8l/100km (17 MPG) which im very far from. As I continue to drive, should it go down or is this it? Because I've been driving like a grandma lol.

Plus, the reason I left the ecodiesel was because 1) the engine blew at 30,000km (18,600 Miles) and 2) it took like 3 business days for the turbo to spool up and I really wanted the power of a gas engine.
 
Hey guys, quick question. This is my first 5.7 Hemi (just traded my EcoDiesel for a 2019 Ram Rebel) and I've got around 1,100km (683 Miles) and I have an economy of 18L/100km (13 MPG). I don't expect a diesel-like fuel economy but the window sticker claims it can do 13.8l/100km (17 MPG) which im very far from. As I continue to drive, should it go down or is this it? Because I've been driving like a grandma lol.

Plus, the reason I left the ecodiesel was because 1) the engine blew at 30,000km (18,600 Miles) and 2) it took like 3 business days for the turbo to spool up and I really wanted the power of a gas engine.
Even a Rebel should do a bit better, there's a few on here with them who are down at your levels and there's some who state they see up to like 17. Depends on the # of miles (supposed to slowly improve), speeds etc. Hopefully you will see better than 13 though.
Either way, enjoy your truck! What's the difference annually for 2-3 mpg gain? It's not pennies but still, you didn't buy a Rebel for mpg. Fun per mile (fpg) is more like it!
 
Hey guys, quick question. This is my first 5.7 Hemi (just traded my EcoDiesel for a 2019 Ram Rebel) and I've got around 1,100km (683 Miles) and I have an economy of 18L/100km (13 MPG). I don't expect a diesel-like fuel economy but the window sticker claims it can do 13.8l/100km (17 MPG) which im very far from. As I continue to drive, should it go down or is this it? Because I've been driving like a grandma lol.

Plus, the reason I left the ecodiesel was because 1) the engine blew at 30,000km (18,600 Miles) and 2) it took like 3 business days for the turbo to spool up and I really wanted the power of a gas engine.
Some will tell you "yes it will get better with more mileage"... My experience with the same truck (same year) with 3600 miles, is no - mine has not got any better...

I'm averaging high 12s low 13s... Have not got better than mid 13s.

This is combo highway and street - 60mi per weekday.
 
Rebel gas mileage was pissing me off so much I had to buy a Jeep, lift it and throw on 37s to get some decent mileage in my daily driver. :censored:

Rebel, leveled, otherwise stock: 12 city, 15 hwy (if lucky)
JLUR, 2.5" MC lift, 37" Pats.............15 city, 17 hwy
 
I'm averaging 13.9 through the winter..

Still better than the 13.4 I was getting in my tundra in the winter
 
I’m hitting 18-19 now after my first oil change. 17 if I’m really moving


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Hey guys, quick question. This is my first 5.7 Hemi (just traded my EcoDiesel for a 2019 Ram Rebel) and I've got around 1,100km (683 Miles) and I have an economy of 18L/100km (13 MPG). I don't expect a diesel-like fuel economy but the window sticker claims it can do 13.8l/100km (17 MPG) which im very far from. As I continue to drive, should it go down or is this it? Because I've been driving like a grandma lol.

Plus, the reason I left the ecodiesel was because 1) the engine blew at 30,000km (18,600 Miles) and 2) it took like 3 business days for the turbo to spool up and I really wanted the power of a gas engine.

I have almost 11000km on mine, just had first oil change. Have had my Rebel for 14 months and am avg 15.5L/100km. On the highway I have had it at 12.6. Most of my driving is city 60/40 split.
 
I have almost 11000km on mine, just had first oil change. Have had my Rebel for 14 months and am avg 15.5L/100km. On the highway I have had it at 12.6. Most of my driving is city 60/40 split.
If I'm understanding correctly, you saw a 25% improvement after first oil change?

If that's correct, it's pretty promising. I've been hoping that will be the case for me - since people often say it gets better, but I don't remember it ever being attributed to oil change - although I've always thought that might be it.

I'm approaching 4K miles and plan to get first oil change soon (no later than 5K)
 
If I'm understanding correctly, you saw a 25% improvement after first oil change?

If that's correct, it's pretty promising. I've been hoping that will be the case for me - since people often say it gets better, but I don't remember it ever being attributed to oil change - although I've always thought that might be it.

I'm approaching 4K miles and plan to get first oil change soon (no later than 5K)

This was on the original oil so I guess I will monitor it until the next oil change. I am more than happy with highway mileage as the Rebel(Hemi) sits way higher than my previous Outdoorsman(V6). If you click on my fuelly badge it will give my info.
 
The reason anyone who drives over 60 mph will have a tough time getting the epa numbers listed on your window sticker.
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Did 240 miles 90/20 hyw/city. The hyw was 50 percent 2 lane 60 mph and 50 percent interstate 75mph. Hit the winds wrong both ways maybe15-20 mph quartering headwind going n 5-10 mph on way home. Averaged 17.6. My truck is a 2020 Laramie orp 5.7 no etorque with 3.21. That's about what I would expect. Not great n not bad.
 

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