Questions about improving gas milage
#11
08-15-2011, 11:15 PM
Professional
08 2X4, V6, extended cab, automatic: 14 city, 18 highway, 15 combined. If you have a 6 speed manual it goes up a bit to 16 city, 20 highway, 18 combined.
Check this out:
http://www.fueleconomy.gov/feg/bymake/dodge2008.shtml
I find it interesting the 08 running E85 gets an awesome 9 mpg city!
Check this out:
http://www.fueleconomy.gov/feg/bymake/dodge2008.shtml
I find it interesting the 08 running E85 gets an awesome 9 mpg city!
yikes! 9mpg on e85!
well id say thats a bit off,i run e85 all the time and I get 12.30mpg(on all around driving)....if i set the cruise on the higway my overhead tells me 16-17 most of the time.
#12
08-15-2011, 11:27 PM
Veteran
Join Date: Apr 2011
Location: South Texas
Posts: 452
Likes: 0
Received 0 Likes
on
0 Posts
On my quest to 20 mpg thread, I will be updating soon, I list some mods you can do to help.
Here's the stuff that has proven to HELP and not hurt, so far.
1. A properly designed intake - with a shield to make it a HOT air intake on cooler mornings, and reversing the shield makes it a COLD air intake for those towing situations/extreme heat. The HOT air intake helps the engine get to running speed quicker, helping it to increase timing faster, and use less fuel thusly, to get where you're going.
2. A basic Chin Spoiler. I have one that goes down about 4 inches down from the bumper to basically be the same clearance as the frame and crossmembers.
3. An electric fan. I haven't done this yet, but it HAS to be an increase. Losing parasitic drag.
4. A cover over the bed is shown time and again to increase your mpg's. I recommend just getting a simple cheapo one that isn't much weight and is very tight across the top with NO ridges. I actually have a hard fiberglass one, which is very heavy, but is also aerodynamically the best other than an "aerocap" (google it)
5. Exhaust. A properly designed exhaust CAN increase your mileage, but believe me, no one really gets much more out of it cuz they can't keep their foot outta it. I believe our exhaust is a 2 1/4" and really that's plenty for our trucks. I would just get rid of the resonators and the muffler and get something like a cherry bomb or other straight piped muffler to replace them. That would be the best. Actually, the best for MPG's would be to get equal length headers and a performance Y pipe down to your 2 1/2" exhaust straight as possible out the back. Depends on how much money you want to spend.
5. Synthetic Oil. Proven 1 mpg in almost any vehicle. Minimum. Do the math. Longer times between changes and better mpgs. WIN WIN except for like 5 bucks more for the change.
Blue
Here's the stuff that has proven to HELP and not hurt, so far.
1. A properly designed intake - with a shield to make it a HOT air intake on cooler mornings, and reversing the shield makes it a COLD air intake for those towing situations/extreme heat. The HOT air intake helps the engine get to running speed quicker, helping it to increase timing faster, and use less fuel thusly, to get where you're going.
2. A basic Chin Spoiler. I have one that goes down about 4 inches down from the bumper to basically be the same clearance as the frame and crossmembers.
3. An electric fan. I haven't done this yet, but it HAS to be an increase. Losing parasitic drag.
4. A cover over the bed is shown time and again to increase your mpg's. I recommend just getting a simple cheapo one that isn't much weight and is very tight across the top with NO ridges. I actually have a hard fiberglass one, which is very heavy, but is also aerodynamically the best other than an "aerocap" (google it)
5. Exhaust. A properly designed exhaust CAN increase your mileage, but believe me, no one really gets much more out of it cuz they can't keep their foot outta it. I believe our exhaust is a 2 1/4" and really that's plenty for our trucks. I would just get rid of the resonators and the muffler and get something like a cherry bomb or other straight piped muffler to replace them. That would be the best. Actually, the best for MPG's would be to get equal length headers and a performance Y pipe down to your 2 1/2" exhaust straight as possible out the back. Depends on how much money you want to spend.
5. Synthetic Oil. Proven 1 mpg in almost any vehicle. Minimum. Do the math. Longer times between changes and better mpgs. WIN WIN except for like 5 bucks more for the change.
Blue
2. Chin spoiler. Still waiting in a write up and pics on that one.
3. The e fan was the single best milage mod I've made. I don't have any numbers calculated but an working on it.
4. Bed covers work but aren't cost effective.
5. Kind of, a restrictive exaust provides more back pressure and more low end torque so you wont lay into the throttle as much. However to much restriction will reduce engine efficency at hwy speeds. Best set up should be equal length long tubes with a 2.25" collectors into a 2.5" pipes w/ high flow cats into an x-pipe then directly into a y-pipe with a single 3" outlet ending in a straight through muffler. Not very cost effective either.
6. Low viscosity synthetic, 0w20 or 0w30 keeps pumping losses low. As long as one doesn't tow or haul.
A higher temp thermostat will help too. Only problem is the increased risk of knocking and pinging.
An underdrive pulley helps as well. The engine does less work turning the accesories.
Last edited by wingman_214; 08-16-2011 at 07:35 AM.
#13
08-16-2011, 12:37 AM
3.7L Club Cab RWD Auto, at 95% city/5% highway, I went from 14.6 mpg hand-calculated average to 15.9 mpg using this technique alone. Extended my tank from about 270 miles to just shy of 300, sometimes even exceeding the 300 mark on a few occasions. Most fill-ups take about 18.5 gallons.
Also, if you can keep it at 60 on the highway (speed I've found at which the slightest pressure on the throttle tends to settle at, on level ground), you can get above 20 mpg. I saw 21.5 once on a 300 mile trip, still had about a quarter tank left.
#14
08-16-2011, 08:46 AM
Join Date: Jul 2011
Location: Peterborough Ontario Canada
Posts: 71
Likes: 0
Received 0 Likes
on
0 Posts
#15
08-16-2011, 08:51 AM
I would start with your fluids. I changed my oil, front and rear diffs over to Royal Purple and I'm getting 1-2 mpg better than before. I also added a K&n intake, custom cat back exhaust and a superchips programmer with 91 octane tune and I'm getting 19.5-20.5mpg consistently. Also take into account that I live in Vt so there isn't much "city" driver where I live.
#16
08-16-2011, 08:53 AM
#17
08-16-2011, 10:28 AM
Veteran
Join Date: Jul 2011
Location: Michigan
Posts: 279
Likes: 0
Received 0 Likes
on
0 Posts
More driving techniques:
When parking try to park where you can pull through, so when you leave you can drive away, rather than having to use gas to reverse out of the spot and then move.
Look ahead to the next light and learn to time your speed to the light. No point in rushing up to a red light just to sit there at idle, or maybe you can speed up a couple MPH and get through before it turns red. Using your brakes is wasting gas, coast when you can, but please don't be so extreme you cause accidents by invoking road rage. Plus less brake usage gives your pads a longer life.
Carry as little weight as possible. I'm not saying leave your spare tire at home but take the tire chains out in the summer. Some have gone so far as removing the back seats in the extended cab models. Maybe leave your tailgate off, etc.
When facing a strong headwind on the highway I tuck in behind a semi. It's a tough balance drafting a semi, you gotta find the sweet spot so your not tailgating and give yourself some reaction time if one of the tire treads separates.
When parking try to park where you can pull through, so when you leave you can drive away, rather than having to use gas to reverse out of the spot and then move.
Look ahead to the next light and learn to time your speed to the light. No point in rushing up to a red light just to sit there at idle, or maybe you can speed up a couple MPH and get through before it turns red. Using your brakes is wasting gas, coast when you can, but please don't be so extreme you cause accidents by invoking road rage. Plus less brake usage gives your pads a longer life.
Carry as little weight as possible. I'm not saying leave your spare tire at home but take the tire chains out in the summer. Some have gone so far as removing the back seats in the extended cab models. Maybe leave your tailgate off, etc.
When facing a strong headwind on the highway I tuck in behind a semi. It's a tough balance drafting a semi, you gotta find the sweet spot so your not tailgating and give yourself some reaction time if one of the tire treads separates.
#18
08-16-2011, 11:41 AM
Record Breaker
I spit out my coffee when I read +10 mpg..I didnt actually have coffee but you get my point. There isnt much we can do to improve MPG. Just keep your tire pressures at atleast 35, which is what is recommended, and make sure your truck is serviced when it should be by either yourself or a professional.
#19
08-16-2011, 12:10 PM
Yeah 10 mpg is craziness. 
I usually norm 16-21mpg depending on my driving, if I am hauling and where I am at, and what fuel I am using. Lately I have been pulling 17s and that's mostly city. I just started tracking it again with aCar to see how it is doing and what gas station gives me better economy.
I usually norm 16-21mpg depending on my driving, if I am hauling and where I am at, and what fuel I am using. Lately I have been pulling 17s and that's mostly city. I just started tracking it again with aCar to see how it is doing and what gas station gives me better economy.
#20
08-16-2011, 01:05 PM
Veteran
Join Date: Jul 2011
Location: Michigan
Posts: 279
Likes: 0
Received 0 Likes
on
0 Posts
Is this due to the fuel mixture? I thought the mixtures were all the same form the refinery? Though depending on where you live you might end up with fuel from different refineries. Which is how one of my local stations "Loves" competes, they don't contract and buy from whomever is cheapest.Do you have a plan to account for Summer and Winter fuel mixtures? Or just figure the best MPG summer mixture is also likely the best MPG winter mix?
I just downloaded the app an placed it next to my gasbuddy app.
Neat!Was there a thread I missed about this?