LoL

 

Usually 65. The speed limits are around 70 and I cant stand to do less then 65. so 60 might get me a little better mileage, I just can't do that on long trips. I have gotten 21-22 mpg doing 60 to 65. I fas following someone pulling a heavy load. I usually use cruise control. It might be better with out, but I don't mess with it. The 21-22 was hand calculated and by my computer. The only time my computer is right or close to right is when I run my tank empty to about 2 or less gallons.

 

I think the average cruising speed on the highways up here are 75-80... limit is 65. No cop bothers to pull you over unless you are doing over 80. Drive any slower you are liable to get run over. Its funny in CT, you get one point on your licence if you are speeding, two if you are going too slow. Cruise control is bad around here because there are so many hills... hills kill your fuel economy with the cruise control. Flat sections of road, like in the mid west and central regions of the US, cruise control works better.

 

60-65 or right around 2000rpms. I think the rpm's are the key.

 

3.55 Gears, no flat roads in northern NJ

50 MPH= 19-20
65 MPH = 17-18
75 MPH = 15-16
85 + = Who Cares

 

Edmunds did some tests on cruise control and MPG:

http://www.edmunds.com/advice/fuelec...2/article.html

The two guys who started the MegaSquirt EFI project
created this Java Calculator for estimating how MPG
changes with speed, weight, tire air pressure and engine efficiency:

http://www.bgsoflex.com/mpg.html

for a 2003+ Ram
use the following:

Coefficient of Drag = 0.528 for Ram 4x4 (maybe 0.49 for 2wd)

Frontal Area = 35.1 square feet

Weight will be from 4900 to 6400 lbs depending on model

Engine Brake Specific Fuel Consumption will be about 0.0567 gals/hp-hour
for the 5.7 V8

Drivetain loss of 12 to 16 % is in the ball park for automatic transmissions
with the torque converter locked up,
but will be a little less for a manual transmission.
Raise this number a little for 3.92, 4.10 and 4.56 differentials where the gear teeth rub more and create more friction.

The Bowling and Grippo calculator does not have an adjustment
for head, tail and side winds
but those do greatly affect MPG.

The amount of heat in a gallon of gasoline varies from
Winter to Summer blends,
and which of the EPA regions you are in (RFG)
and with the amount of alcohol blended in.
Change the BSFC up or down about 15% depending on how good or bad your local gasoline is.

 

i have an 06 and I just drove from pensacola to va bch last night... I averaged about 16-17 when i was going 70-75 and 22-23 when i was going 65...

 

13.5mpg......doesnt matter if I am doint 70 or 80. My 5.9 just drinks fuel regaurdless. I get my best milage going downhill, it's just coming up the other end...LOL

 

Most of the stuff ion those tests I have been doing for years. I still wave and smile while people blow past me on the horn and sporting a bird. I'll get there when I get there. I have to say my trip out to Yellowstone a few weeks ago was a rare exception to my driving habits where I was going way faster than normal. Some of the speed limits were 75 but most of them were 65 - 70. I am not sure whether I went much above 75, even when I could legally drive 75, but I noticed I was driving about an average of 65 mph which yielded a fuel ecomomy rating of 19.9 mpg. Now I will state on the 65 average this is also factoring in the speeds I was doing while driving in the national parks and at some times just about an idle speed on my truck. The 19.9 also factors in idling in traffic, start and stop traffic, etc... I love the Ram and it's mileage is pretty good on the highway but when it comes to city driving the mileage sucks. My mileage it now averaging about 14mpg and it's been city driving for the most part over the past 2 weeks.

 

yeah i agree the ram gets damn good gas mileage... i was riding back to va from fla with a friend of mine who has an 06 silverado... he was only getting 18 at 65 and about 14-15 at 70-75... i am not sure how much the MDS on my truck has to do with the mileage... that could be what keeps the mileage good at 65... I believe the rpms are too high when i go 70 for the MDS to cut on