2008 Tacoma w/lift : MPG and Engine noise.

when you compute the millage, gotta ask did you throw in the error for the big tires?
sitting that tall with bigger tires you gas millage is going to be bad
and engine is going to be working hard at highway speed with the gearing difference of the tires and the aero package of a barn door.

you have a megaflow muffler have you checked the exhaust for leaks?
still have the cats on it? if answer is no then you have changed the torque curve for your engine

The loss in gas mileage might be due to the tires. I noticed a drop myself when I changed from the stock Rugged Trails to Mud Terrain KM2s, and that's still with stock suspension.

No exhaust leaks that I can find. As for the difference in speedo i took that into concideration, was my first thought. Even still I have seen alot of posts on here from people with the same setup gettin 16ish mpg

YKTaco said:

The loss in gas mileage might be due to the tires. I noticed a drop myself when I changed from the stock Rugged Trails to Mud Terrain KM2s, and that's still with stock suspension.

Click to expand...

That could be some of it.... I need to look into different tire and tread patterns, maybe something a little less aggressive

if you still have a stock spare, weigh it, then weigh one of your 35 in tires
that is all rolling mass that requires horsepower to turn

and upgraded breaks to stop