I have a 2006 with 33,000 miles. I drive 70 miles a day to and from work in hellish traffic. I get to open it up on the tollway for about 15 miles between the two toll stations and then the two break checks where the cops are "hiding" every Monday - Friday.

I know I need to change the new plugsthatI already purchased. That should help a bit. However, the question is.....

I amgetting steadily between 14.5 and 15.5 mpg. I use 91 or 93 octane,mainly 93 because it is cheaper than 91 purchased anywhere except Sam's.

We all have various MODSbut specifically the Hemi - What is everyone's average MPG?

Scott

 

This topic has been discussed several times. Here are some threads on this topic via search for "MPG" from the top menu.
https://dodgeforum.com/m_780015/tm.htm
https://dodgeforum.com/m_408905/tm.htm
https://dodgeforum.com/m_937782/tm.htm
https://dodgeforum.com/m_240025/tm.htm
https://dodgeforum.com/m_950596/tm.htm

 

Thank you - I searched and a lot popped up. I read quite a few threads and reposted the subject for what appears the 10th time.I read so many post that I know some could not be hemi's. Your posthelped. I probably have a heavy foot and driving in stop and go traffic blows. I like the idea ofMobil 1. That is not the first time I heard the suggestion with an increase in gas mileage.

 

DO you have a reg. station you get gas at? we did and that was the problem,we switched to another and mileage went up 2mpg .The car has 33,000 miles headers,ram air,and we have never changed the plugs yet or fuel filter and are getting about 18mpg on the ave. 87oct

 

It is about 50/50 at Sam's (93)and Randall's. I seem to get better mileage now that I think about itfrom the lower grade (91) at Randall's. I studied my driving habits this week. I sit in trafficwith the slap stick waiting for a chance to step and them when the traffic opens I take advantage.

Thanks
Scott

 

I average about 14.5 and the worse I have seen is 12.5. I have driven it on open freeway for about 140 miles at 65mph and got 22.71. If you are in traffic then 14-15 is not bad at all. Only way you will get any better will make the car boring to drive. I have 18,000 miles on mine and soon going to change the plugs I do not think that will increase mileage but want to make sure mine runs its best at all times. I use 92 Supreme 76 and that makes her the most happy...

 

You will get better mileage if you put the transmission selector in D - especially in the stop and go traffic. Using the Autostick puts the engine in 8 cylinder mode all the time. With the transmission selector in D, you will enable MDS and switch to 4 Cyl mode when you don't need the power.

That's the only thing Chevy V8s have over the Hemi w/MDS - there is an 4/8 cyl indicator in the instrument cluster so you can adjust your driving pattern if you want the economy of 4 cylinders when there are no Mustang GTs around.

 

The MDS system sucks. I can tell when mine is on by the sound of the engine. They claim a ten percent boost in mileage. I drove it like a baby and got 22.71 miles per gallon. I might have gotten 2 miles more per gallon with the MDS? that means that it does almost nothing at the low end around town driving. I have noticed that if you drive your car hard it will go into the MDS mode less often but that is another story. If I have my way I would have chosen to shove that MDS system up theDodge engineers rear-end because it makes it more difficult to make mods to the engine (cam/lifter/programming).

I do not know if the FRONT WHEEL drive Chevy's offer better gas mileage in real life situations but I garuntee one thing that those cars will never last long... Try putting another size engine in a 2006 Impala!! When my Charger gets old I am going to put a larger engine in it liek a 440 Magnum.

 

Well the MDS does work and work good. I made a trip to Dallas from south of Houston and averaged 25mpg up there. It was Raining and was babying the car.On the way back I averaged 23.6mpg. That was a speed of 75 to 85 and a few 100 plus runs along the way.If you have the Hemi car, as I do, get a Superchips Flashpack , it will kick the MDS in sooner and make your milage get better if you stay "out of it"
Another thing I have noticed, check the fuel for methanol content, It made my milage go down drastically about 6 months ago.I have since NEVER used that staion again and milage is back where it was before.The fuel I use now contains no more than 10% Methanol.

Scott

 

I have a Superchips and no cats. I have not noticed the MDS kicking in at all unless I am going down hill coasting. I live in Seattle and its nothing but hills. Even the freeway is up and down and the MDS kicks in maybe 5% of the time I am driving. I will diable it all. It limits your cam options....

If the MDS was an otion I would have gone without it. I have driven my car in D and using the auto stick and in my situation it dilivers the same gas mileasge. I would have to drive 10mph at all times to improve my mileage here. When I drive my car like an old man I get 15mpg, if I drive it how I like to I get 14mpg... I take the loss!!