Bad gas milage

Ok so iv got a 2010 tacoma that i bought brand new.
When i got it i was able to get around 500km or so with the stock wheels and tires. 265/65/17.
Since then i have put a leveling kit on it some wheels and tires.275/70/18 the tires are duratrack 10 ply tires.
and i also added a truxedo cover to help out there.
And now im only getting about 350km per tank.
thats a brutal loss of miles per gallon.
i know the wheels i have are preatty heavy but still.
iv also recently added a magnaflow free flow stainless muffler.

 

all your add-ons will kill the mpg. I've gone through this in truck after truck, full size, mid size and every brand of truck (I've owned 11 new vehicles in the past 13 years!).

Every time I started modding things; and tires, level/lift, CAI and exhaust are always first, the mpg goes in the pooper....every single time.

I just got - last week - a 2011 4DR 4x4 Sport w/ every option and am tryiing my hardest to keep from modding it and see how the mpg goes. I just traded in my Titan which I modded the crap out of and mpg went to from about 18mpg to about 9.

 

duracraps will kill your gas milage. They are some damn heavy tires

 

duracraps? first time I've heard anyone call them that. They're great tires.

I get about 15-16 mpg with my 285 duratracs (8ply), 2.5" lift, and a thule roof rack.