Gas Mileage Issue

For the last month, my gas mileage has consistently been dropping every time I fill up. I used to get around 20-23mpg (city/hwy combo) and last night when I got gas it was a whopping 13mpg.

There are no mods to the truck. The air filter is clean, tire pressure is good, as well as all regular maintenance done.

Anyone have any suggestions as to why my gas mileage is decreasing with each passing day?

 

get a dyno done if its in warranty take it in.. mine has gone down in the last couple weeks too winter blend maybe? but yours is a huge loss

 

How many miles do you have on your truck? Have you replaced the fuel filter? Spark plugs?

13mpg is really bad. In my 05, I have been consistently getting 17.5 city and that is with the 10% Ethanol..

 

I'm guessing you double checked your math after figuring that...that is a huge drop...

Not sure what that could be unless something like spark plugs have gone south. I have a 2005 TRD DC in which the mileage has been improving lately, now between 19 and 20 mpg...

 

heavy foot

 

i just went thru my "new to me" truck, changed the f/r dif oil, transfer case oil, plugs, K&N filter, aired my tires up to 35 and reset the ecu, i do combined city/highway about 20% city 80% highway rarely go over 2500rpms and i'm still getting just over 16 WTF

so OP i'm lookin for the same answers as you lol

 

has the weather changed dramatically? colder weather = fewer mpg

 

Cold Weather = winter = winter blend = shitty mileage

 

It is ashame they add ethonol to your gas and it causes poor fuel mileage! It is getting harder and harder to find stations that have 100% gas anymore. You can use this link to find 100% gas in your state...

http://pure-gas.org/index.jsp?stateprov=TN

Better hurry while you can cause I think it won't be long before you won't be able to buy 100% gas. Also, you need to use Marine Sta-bil in weed eaters, leaf blowers, chain saws, etc., if you are using the 10% ethanol crap in your gas mix. The ethanol will prevent the oil from mixing very well and will eventualy cause engine failure. That is our super smart government working hard for us!

 

Check your alignment...

 

I have kept the truck maintained by the book actually. I am pretty ocd when it comes to my vehicles and so this is very troubling. Checked the spark plugs and they are still in very good condition. I typically don't drive with a heavy foot and especially not now. I can't afford to drive with a heavy foot at 13mpg. Last time I filled up I got 218 miles out of a tank and here in southern california gas isn't cheap. Right now, my truck has about 70,000 miles on it.

 

Yeah and the EPA wants to push E15 now...

 

Ive always got around 13-14 mpgs

 

I have yet to get more then 14-16 mpg in my 2010 dcab auto and that was before the 3" lift. And that's with light driving mostly city. I only have alittle over 6k miles on mine so I'm hoping it's just "not broken in" yet. So I feel your pain OP.

 

wowwwwwwwwwwwwwwwwwwww

 

i average about 10-13 mpg....

 

If your logs are right you dropped about 45% mpg in a tank. Winter blend is piss, but not that bad and you may not even get that in CA. Have you noticed any drivability issues? Plugs, filters wouldn't likely cause that big a change in a short time. You might have gotten a really bad tank of watered gas, but that should have given drive problems. Did you buy the tank that gave this (not the one you calculated from, the one before) at a different station? In Mexico?

For this big of a difference I'd look at two things:
1) Tank before last was not a fill.
2) Siphon, leak, or draining

Are you ready for another fill yet?

 

So Cal city traffic driving like a granny I get 14-15mpg.
Sucks, but it's a truck. Remember the sticker for these trucks (V6) states 16-19mpg.

 

I can not believe that you guys are getting that kind of mileage. That's ridiculous. I can't remember the last time I got below 20 mpg on a tank of gas. I usually get about 360 miles on a 17 or 17.5 gallon fill up.