Poor MPG . Dealer says live with it.
 

This is a follow up to my last thread, LED (average miles per gallon).
I Recently bought my 2007 Aspen 5.7 Hemi with 4 wheel drive with only 33,000 mi into the Chrysler Dealer after trying numerous things to get better gas milage like,
Change air filter, useing fuel injecter additive, and keeping tires properly inflated. My truck runs fine smooth as can be only problem, I only average 9 miles per gallon. The dealer said thats what these trucks get. It upsets me that he changed my oil kept the truck for 4 hours and gave it back and said Everythings Fine now pay the cashier 38.00 for the oil change. The Clerk at the service counter says that normal for city driving with my aspen. To me thats not normal. I would expect to get at least 12 to 14 mpg . Does anybody have ideas what tests should have been done to my truck to determine that all is well at a dealer. I will try anything to get a few more miles per gallon. Thinking about changing plugs any ideas appreciated.

Have you changed the plugs yet? They're due at 30k miles. A fouled plug can result in poor gas mileage. I get 12-13 in the city.

There's too many variables for anyone to know what's going on with your truck. If you're doing lots of stop and go driving and idling, that greatly affects gas mileage. Your driving habits (how hard you hit the gas pedal!), whether you're using the a/c, type of tires (are they stock?), and even the type of gas you're using affect mileage. If you have the Hemi engine, you should be using midgrade gas. Using 87 absolutely will affect the fuel economy, and using premium is a waste of money.

Most other potential causes (e.g. EGR valve, bad injector, etc.) are unlikely on an engine with 33k miles.

Mixed City for us is 13.3 -- 15. That's with some freeway driving, but also stop & go and idling (while in line to pick up kids from school). Ours is 2wd, and we have aggressive AT tires. I'm guessing we would get 1mpg better with lrr tires. 9 is very low. I would frown also. However, I could see 9mpg if it were all city (small town) driving. How big is your "city"? Do you ever get it up to 60mph, &/or operating temp? I grew up in a small town, and my parents still live in a small town. Speed limits are 25-35. I'm guessing I'd get about 10-12 MPG if I lived there.

I get 14-17 mpg City.....I say go to a different dealer

I too don't get good gas mileage on my 07 Aspen. I was averaging about 10-11 in the city. Yes it was stop and go, commuting about 5 miles each way on city roads (no freeway). Now that I am commuting on the freeway every day I am seeing around 14-15 mpg. (Some stop and go on the freeway due to morning and evening congestion). I would love to see my MPG higher.

I have just noticed lately that my milage has dropped from 17-18 down to 12-13. I have been wondering myself on this. My Emissions box ( charchol) by the tank collasped on itself due to a faulty seal (not covered under warranty) I will check on the plugs.. I have 90k on the truck, but just supprised on the issues adding up in the last 10k miles.

I live in a city area and my typically avg is a 9-10. I changed oil revery 5000 miles and have kept the stock filter. Im thinking of changing over to the K&N one. But When Im back and forth on the freeway i have gotten up to 19 avg. I have the hemi engine as well.
Your in the ball park with your avg.

We are averaging 14-15 city, and get 18-21 on the highway depending on if it is flat highway or hilly.

Stick with your factory air box and paper filter. K & N, along with other oiled filters, let too much particulate through. Our factory air boxes aren't as restricted as other vehicles and get plenty of flow. All you'll be doing is gumming up your throttle body and letting dirt into your engine, which will cause you lots of problems in the long run.

Agreed. They should have checked your plugs as well. Heck, they could have/should have changed them out and charged you for them, too, and I am surprised they didn't.

2007 Aspen MPG
 

Iknow I am coming in late on this reply but is your variable displacement system working normal?? Probably does not matter much if your not on the freeway often enough though. I have also had vehicles before with a partially clogged converter causing poor fuel mileage but also will show up in poor performance too and usually a MIL comes on.
John

Your computer learns your driving style
 

Apparently the Aspen computer learns your "driving style" and adjusts performance accordingly.

Ask your mechanic if simply disconnecting the battery will perform a reset which will cause the computer to "relearn" your habits.

My wifes first 2007 Aspen with the 4.7 would only get about 9-11 around town. I thought it was way underpowered. We had to floor it to maintain speed up an incline. I was totaled and now have an 2008 with the Hemi and it seems to do better on gas so far.

Goodbye Aspen. Hello Mini !!!!!
 

After 2 1/2 years of having the truck that i loved but hated to drive because of the lousy gas mileage, I took my loss and got a 2009 mini cooper clubman. Wont be complaining about gas no more. Dont get me wrong i love my 2000 dodge durango and will keep it forever if possible. My durango with a 5.9 engine Gets better gas mileage than 2007 Aspen w a 5.7 hemi because it can be put into 2 wheel drive when 4 wheel drive is not needed. Aspen had no option always 4 wheel drive always sucking extra gas .

Aspen gas mileage
 

Air temperature makes a big difference for me. 14-15 mpg around town in summer, 6-9 mpg in winter. It goes to -35 here and that really drops the mileage. There are so many variables that can affect mileage. I once read that adding small quantities of acetone to your tank would help. Tried it and actually got 3-4 mpg better on the highway but not sure of long term effects of acetone on the fuel system so quit.

I have a fix for bad gas milage
 

If you want to get better gas mileage in any car you own try this.....Run your gas tank down to a quarter tank of gas....Then go buy two bottles of Chevron Techron Complete Fuel System Cleaner....(AND NO...THIS STUFF DOES NOT HAVE ANY HARMFUL MFT IN IT)....It's safe for all fuel systems.....Add them in the gas tank.....Then go to your gas station and fill your gas tank up.....Drive your car for at least a half an hour and you will watch your gas mileage increase before your eyes......Use this on a regular basis and you will get great gas mileage no matter what car or engine size you have.....PS...It will make your car pass the emissions test in your state everytime....I use it in my Hemi powered 2009 Chrysler Aspen and get a average of 18 around town and 24 on the highway....This is not BS...I'm a thirty year Chrysler tech and I swear by this product...

This is all you bae to do to get better gas milage it worked for me
 

this is all you have to do to get better gasmilge seriously=tnitchov;50375]Apparently the Aspen computer learns your "driving style" and adjusts performance accordingly.

Ask your mechanic if simply disconnecting the battery will perform a reset which will cause the computer to "relearn" your habits.[/QUOTE]

Get a BullDog
 

I live in urban area with tons of stop signs. I installed 2 years ago a BullyDog for the HEMI. On the highway I get 24-26 MPG and city 10-12MPG.
Previously it was 8-9MPG city and maybe 18-19MPG highway.
BullyDogs are expensive. However, coded in America with credible engineers. My payback was 5 months back then.
My car has 166,000 miles.
Essentially they recode when the MDS turns on and various engine parameters.
I also yearly do the seafoam treatment at infeed, inside crank and gasline.