I'm getting a little less mpg's than I used to get. It seems to have started about the time I added the 4" exhaust. Probably about 1 to 2 mpg. I can't swear there is a correlation, thought some of you guys would have some knowledge on back pressure and retro fits.
I recently changed the fuel filter, it was pretty black, no difference in mpg.
Tire pressure and driving habits are the same.

 

If you're anything like me....you started getting into it more when you accelerated so you could hear that new exhaust tone. That could easily drop your mileage 1-2 mpg.

I wouldn't think changing the exhaust would decrease your mileage though. If anything I would expect a decrease....but what do I know.

 

I haven't seen any decrease in mileage.

 

i've seen a drop in fuel economy with my 5" pipes and bhaf/torque tube. loud pipes, heavy foot syndrome...

 

Yep. Machoism and lack of willpower to resist. We all suffer from it. Start carrying the wife around with you more. Her influence will be beneficial to calming that right foot.

 

I got a INSTANT 1 to 2 mpg INCREASE with new exhaust! Driving easy.The downside is that it sounds GOOD and mileage will fall as the foot falls!

 

Well, I did like to listen to it , and it does sound better when you get into it a little, but I'm back to nromal now, but who know normal may have changed

 

After I got mine I was always on the PIPE! more so around any FORD 6.0 .LOL.neighbors thought a BIG RIG was coming down the street.Now I'm back to driving easy and more like a 50 year old.

 

I've had my 4" exhaust for about 3 years now. I still like to get into it and listen to that straight pipe sing.

 

every overpass and retaining wall I pass cause a drop in mpg

I think my rear window motors are getting worn out too!