Just bought a 2009 rubicon 4dr auto
Just added a catback exhaust with 3in pipe for good sound
Then 275/55/20 =32 in tires
Stock gears wich i beleive a 4.10s
Problem is i get 9-10mpg in city
What do i do next?
Im dreaming only that im having a 14mpg jeep :(

Help here is most kindness

 

How much did the 20" wheels add to your unsprung weight? Also, was the 3" exhaust tuned to the correct back pressure? Your stated mileage is pretty low, and those two changes might not be the entire reason, but they're not helping.

Also, what was your mileage before you added new wheels and exhaust?

 

Same mpg before exhaust and exhaust add a tiny torque atleast.
Never weighed the 20+tires and never tried the stock rims.
Nitto tera grappler 275/55/20 its not that heavy i guess its just a/t?
Some forum jeeper advice to change apark plugs, clean theottle body , change fuel filter, and clean fuel lines.
I tried 95 and 97 octane still the same nothing happen. We dont have 87 and 91 in the philippines

 

The cold weather and winter blend fuel is taking a rating on mpg. My 2012 JKU dropped from 17 to below 15. A coworker has a 2012 jkur. His dropped from 15 down to 13.

 

Rob.... Currently its always hot in the philippines
But somethings not right. Stock 32 tires. Rubicon with auto and maybe 4.10s ang having a 10mpg?

 

Doing the spark plug change etc. is not a bad idea. I did mine at 150,000 km and it made no difference, but at least there is maintenance happening. Did you retain the catalytic converter with the new exhaust? I had a plugged up cat on a GMC Suburban that killed the performance and mileage. Not cheap. Does it seem to be running ok?

 

It is possible that the Jeep factory 87 octane engine tune is not working well with your higher octane fuel. A tuner like the SuperChips will at least allow you to tune for 93 octane.

 

With the way I drive and all the stop and go traffic, also factor in the winter blend gas 10-12MPG is the norm for me.
This is where my MPG was at the other day. Short drive back and fourth to work and the cold is just brutal

 

He's in the Philippines so the cold isn't a factor. It is here though. Winter gas and idling to warm up kills it. Filled up today and calculated 13 mpg (17.9 L/100km in canadianese). can't do anything about it. It's -31 here today.

 

Wow pg nice mpg mine sys 25.4L/100km or sometimes it goes to 27-28L/100km with just 32 tires. Yeah winter is not a problem since in the philippines never gets a cold weather