Wierd MPG Readings for 5.7 2500 4x4

[zogg]

The other day we took a trip ftom southern illinois, through st louis, to southern Missouri...a couple of hundred miles each way.

Starting out I reset the mpg meter on the dash, and recorded 17.4-17.8 mpg driving at 62-65 mph going through st louis. Once we got out of town, I ran at 75 mph the rest of the way to our destination. The MPG continually dropped until it hit 14.3, which is where it stayed.

Going through southern Missouri is fairly hilly and the truck geared down quite often...more than expected.

On the return trip, I again reset the mpg meter and after about 30 miles at 75 mph, I was right back to 14.3 mpg.

A we approached st louis, we had to slow back down to 65 mph.....mpg came back up to 17.3 and we finished the trip at 17.6.

I never had a truck that would drop 3+ over a 10 mph range....surprising. we were totally unloaded in 2wd the whole trip.

I am wondering how this compares with the 6.2 L engine in the same truck??????

 

[sandawilliams]

I hate to tell you but on my 3 rams take the evic reading and subtract 2 MPG and that is closer to your real MPG. The evic in these trucks is very un-reliable.

 

[Ratket]

the best I got on a 300 mile trip was 18, and that was with my cruise set at 73. I could of got better on the trip I am currently on but half way through the trip I decided it was go time and let the hemi foot take over.

 

[BULL55]

2014 CC 5.7 4X4 reading on mine most the time a -1 when i do the hard test.

 

[Caldwell]

I cant say im surprised by the mpg difference of 10mph with a truck this large. your fighting that much more wind resistance, and working that little extra bit harder to maintain speed. @ 75mph unless you are going down hill, your not gonna see an ecomode ( does the 5.7L 2500 have that now ? ).

 

[Ratket]

I cant say im surprised by the mpg difference of 10mph with a truck this large. your fighting that much more wind resistance, and working that little extra bit harder to maintain speed. @ 75mph unless you are going down hill, your not gonna see an ecomode ( does the 5.7L 2500 have that now ? ).

I don't think the 5.7 does but I could be wrong. Also on Thursday on the 10fwy headed towards Palm springs with the cruise @ 80mph my mds was active.. witch yes is really suprising, but it was active and it activated quite a bit, the low elevation really helps this thing breathe.

 

[whatroads]

In my 1500 anytime I hit 75 MPH or higher I get a significant drop in MPG. Like others, I would skip the evic and calculate by hand

 

[Arctic-Rodz]

My trucks calculations are off by 2mpg as well. It's optimistic lol.

On a road trip going 75mph my truck said I was getting 20.2 mpg. Hand calculated it was more like 17.8mpg or so. Which I don't think is that bad.

Hand calculate it... then prepare for the horror!

 

[THETANK]

The old saying or calculation was/is for every 6mph over 60 you lose 10% in the mpg dept. Not my saying someone else's calculation so don't yell at me lol

 

[Ratket]

I get rediculous mileage at 65 and under.. but ain't no body got time for that!! lol

 

[THETANK]

I have had the last 3 years to pitter patter and if I live to 80 I have to kill 30 more years in the same fashion,

 

[Zeak]

My mileage seems to drop 2-3 mpg going from 70 - 75. Was the same with my 11' cummins as well. I could get ~20mpg at 70 but more like 16-18 at 75 with that truck. Probably about the same with my Outdoorsman 1500 i have now.

I would like to have 70mph speed limits back but they are probably more likely to go to 80.

 

[Ratket]

not here in Cali... we have a ton of hwy and those can be 55mph.. 90% of stuff here is 65mph..

 

[Zeak]

Yeah, 90% here, at least where I live and travel, is 75 and a couple highways are 80. Even small 2 lane highways are 75. Maybe it is people like me saying people like you have bogus mileage claims but it's just highway speeds. I can easily get 20+ mpg at 55-65 but a huge hit above 70. I only got 11.9 mpg highway going 200 miles north to Amarillo for Christmas. That was going close to 80 with 30 mph wind coming at me though.

 

[Arctic-Rodz]

75MPH got 18mpg on my cummins!

and that's hand calculated

 

[Ratket]

noice

 

[warwagon98xj]

The 2014 5.7 has the 4cyl mode

 

[Mr. Crowley]

Yeah, once I get above 65 the mileage definitely drops.
Trying to push something that big, heavy, and un-aerodynamic through the wind takes a lot.
...it will drop even more if you are unlucky enough to have a headwind.

 

[loveracing1988]

The 2014 5.7 has the 4cyl mode

Says who? The brochure I have says otherwise.

 

[regularcab2500]

The 2014 5.7 has the 4cyl mode

Only in a 1500.