MPGs are down from 18-20 to 13-15... WTF

My MPGs has been slowly falling apart.. in the past few months it has slowly decreased... last two fill ups i have had MPGs between 13-15

 

how many miles do you have? Hows your air clear? Did you change your spark plugs at 30,000?

 

Lift bigger tires?

 

just hit 30K like a week ago

 

Ill have to check it out tomorrow.. what kind of Spark Plugs do you recommend

 

I just hit the same... 32K and my mileage went to shit! 13 city and 15-16 highway on last three tanks. Actually has me thinking why not drive a full size??? Really, the plugs need replaced at 30K? This one has me interested.

 

They say change them at 30k but they use a copper plug, when I change mine it's getting platinums so I dont have to do it again

 

platinums or not your gunna have to regap them regardless, maysell put stock ones in and just change em yourself every 30 k

 

platinums last longer and I dont see myself owning this truck longer than 75,000 mi

 

If you have to pull them to re-gap them at 30,000mi, might as well just replace them.

Expensive multi-tip platinum wonders are a bit of a waste on these engines.

 

Lead foot? I'm at 30k with a sc and I'm getting about 14.8 with a heavy foot

 

Change your plugs John. Make sure the new ones are gapped at .040-.043,and go with the stock plugs.platinum won't do anything for these motors....and unless you are sc'd.....the iridiums won't either.

 

thanks will

 

your tuck will do the same thing when you hit 60,ooo or so. I just hit 57ooo on my 2008 and the mpg has dropped off. Just need new plugs and ill get back what I have lost.