I recently purchased a 2007 Aspen with a 5.7 hemi with 30,000 miles.
My Question to anyone that could answer it is my LED average miles per
gallon never gives me more than 8.9 miles per gal. Does anyone out there get the same average Or should i bring my truck in for service to get this fixed I know im geting more than 8.9 mpg at least 13 to 14 city as stated in manuals. My Chrysler warranty is good to Nov 2010. Dont know if i should bring it in to them. Any Answers much appreciated

 

Either the previous owner took very short trips and/or drove aggressively, or the vehicle spent a lot of time on and idling at the dealer before being sold. You need to reset the average MPG by pressing and holding the RESET button for two seconds. You'll know immediately if it worked, because the display will show dashes. You can also do a global reset for average MPG, elapsed time, and trip. Press RESET twice within two seconds while any of these items are displayed will reset all of them.

If, after all of that, your average mileage continues to be dismal on the display, calculate it yourself for a tank of gas. If you're at less than 12-14, you might need additional service.

Good luck!

 

In reply to doing the gas measuring have been doing that already I got my answer tonight. I put 20 gallons of gas reset both led one on speedometer trip mileage and the other led avg miles per gal they both came to the same results.
I only got 9 miles per gallon. i drove 180 miles(trip reading led) My gas light came on like it did when i reset both led's to zero. And looked at my avg miles per gal led and it says 9.0avg mpg. I dont understand why i am not getting better gas miles? Truck runs fine no knocking smooth like new. Like i said earlier i have a warranty. Is there any thing i should do myself before i present this to Chrysler or is this normal which i am scared to hear?

 

If you're doing nearly 100% city driving and sitting at stoplights for extended periods of time, it's possible. There's no way to answer your question without knowing your driving habits and city/hwy mix.

I can tell you that we have a 70/30 highway/city mix (approx), and get around 14 mpg or so.

 

I am mostly driving city I would say 90%. Still expected more mileage from a 5.7 hemi. My 2000 Durango with a 5.9 gives me 12 city for the longest time but this case is not over yet. Today i got a 9.6 avg so i think its geting better hope so anyway. Will keep you posted after this 20 gallon test result if you like. Thank you for responding.

 

Our average in town is between 14-5 and 16.3 the average on the highway is 19.8 to 24.2. Overall very pleased with gas mileage. This is from the on-board computer and is within 5% of manually calculated gas mileage.

 

Aren't the Hemi Motors required to use a Mid-Grade or Premium fuel? My Ram has a Hemi-MDS and it requires Mid-Grade fuel to get the posted fuel mileage.

 

What type of gas is everyone using or what is required without looking in my owners manual? My avg is still 8 to 9 mpg city only and i am not gunning the pedal. Any ideas from anyone much appreciated.




2007 Aspen 5.7 Hemi fully loaded 30.000 mi.

 

2008 manual, pages 331/332:

FUEL REQUIREMENTS

All engines (except 5.7L engines) are designed
to meet all emissions regulations
and provide excellent fuel economy and
performance when using high quality unleaded
“regular” gasoline having an octane
rating of 87. The use of premium
gasoline is not recommended. Under normal conditions,
the use of premium gasoline will not provide a benefit
over high quality regular gasolines, and in some circumstances
may result in poorer performance.

The 5.7L engine is designed to meet all
emissions regulations and provide satisfactory
fuel economy and performance when
using high quality unleaded gasoline having
an octane range of 87 to 89. The manufacturer
recommends the use of 89 octane
for optimum performance. The use of premium gasoline
is not recommended. Under normal conditions, the use of
premium gasoline will not provide a benefit over high
quality regular and mid-grade gasolines, and in some
circumstances may result in poorer performance.

Light spark knock at low engine speeds is not harmful to
your engine. However, continued heavy spark knock at
high speeds can cause damage and immediate service is
required. Poor quality gasoline can cause problems such
as hard starting, stalling, and hesitations. If you experience
these symptoms, try another brand of gasoline
before considering service for the vehicle.

 

I have an 07, and throwing 2 bottles of fuel system cleaner into a full tank helped my fuel milegage. Also, use decent fuel. Stay away from the Circle K's... stick with the Chevrons n Texacos. It makes a difference.