GMC Truck Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
134 Posts
Discussion Starter #1
so since ive owned my truck its always showed 17.7 miles per gallon as my average fuel economy. well it had been slowing dropping so i decided to change oil using mobile one 5w/30. cleaned my air fileter and the mass airflow sensor. havent had a chance to change my fuel filter as its in the tank. After doing all this i figured it would improve alittle but nothing its still dropping. its at 16.5. Its an 05 ecsb 5.3 2wd. I also just started using premium fuel as well. Does anybody have a clue what i need to do?
 

·
Registered
Joined
·
5,528 Posts
First of all, don't trust that thing at all. I have had it be dead nuts on point and be very wrong. Go old school. Fill up, reset your trip meter. At the next fil up, compare the gallons you put in to the mileage. You have done all the right things, but do include a tire pressure check, clean your throttle body, search "seafoam" on this site and look at the longer threads for instructions.
 

·
Registered
Joined
·
2,723 Posts
I thought the fuel filters were on the frame rail on the driver's side? I believe it is on my 04, maybe they changed it.

Covah gaves some great advice. Follow it, and report back if you still do not see a difference.
 

·
Banned
Joined
·
6,955 Posts
get a new air intake system. that always helps. and maybe some new plugs and shit are in order. Just do a general tune up of the truck.
 

·
AllOffTopic.com FTW!
Joined
·
8,460 Posts
As Covah said, divide your miles traveled by your gallons put in, and if you want it to be reasonably accurate fill at the same pump and don't top off. That's the best way to determine if your fuel economy has really changed.

Check for:
  • dragging brakes or wheel bearings
  • fuel formula has changed (winter blend to summer blend, maybe -- most of the time the winter blend is worse but maybe your truck likes it...or maybe your area recently changed from MTBE to 10% Ethanol as the additive)
  • roads or traffic condition change - new pavement, different route to work, lots of traffic from a new shopping center
Got a check engine light/any codes?

Those are the things I can think of off the top of my head, in addition to the other suggestions above mine (tire pressure, etc).
 

·
Registered
Joined
·
134 Posts
Discussion Starter #6
gm changed the fuel filter location in 05 to in the tank. Sucks cause now it's gonna take alittle longer to change now.
 
1 - 6 of 6 Posts
Top