I had a 2" lift and rubicon shocks installed on my 2009 Jk about a month ago and will have 33" tires put in January.

I have lost about 3 mpg since the lift while still running stock wheels and tires with 95% city driving. I would have to think that the lift and drop in mileage is unrelated and just coincidental? I was getting about 17.5 in the city and now getting about 14.7.

Thanks for your input!

 

My guess would be might have something to do with aerodynamics, but hopefully someone more knowledgable than me will chime in. I lost 2-3 mpg just by replacing my factory bumper with an XRC, that was even before I put the winch on and factory tires/wheels....

 

Well I am going to go with the same chaos 5 wheel and tire size you have so I assume I will lose more mpg.

 

Not sure if this would effect it but did you get the Jeep aligned afterwards? or have the alignement checked?

 

I was going to an alignment after the new tires and wheels are installed. The steering wheel is about 4 degrees off when driving straight.

 

You went from a brick to a lifted brick. But yes, a 3 mpg loss sounds like more than I would expect from a 2" lift using the same tires. Did you remove the plastic air dam/skid under the front bumper?


For the alignment, the only things a shop can do is center the steering wheel (which will take a wrench and less than 5 minutes of your time), and adjust the toe-in (which was not affected). Go down to the write-ups area and find the DIY Alignment writeup. There is an index stickied at the top.

 

No, not yet.

 

I understand that mods decrease mpg and it is worth it to me, I just wanted to rule out anything mechanical.

 

Guys, I posted this reply in another thread (link below) about MPG...

There are some things you will find true to "gas mileage" affects on all JK Jeeps, no matter what engine. Lifting 3" will net you NEGATIVE 1 to 2 MPG. Running 35 inch tires and wheels will have the same NEGATIVE effect of 2 to 4 MPG. Bumpers, wench, skid plates and gear will also net you NEGATIVE 1 to 2 MPG. Do the math, this will take a JK that can get possibly 20 MPG from the factory into the average 12 to 16 range in MPG according to the mods performed. Of course this is related to your location (atlitude and geography) and driving habits. It is the extra weight, tire diameter and wind resistance causing the MPG loss, all physics laws that cannot be avoided. Most modders then regear and perform engine performance mods (i.e. ECU programming, superchargers, headers etc.) to get the engine back into it's power band and better operation efficiency to account for this negative physics effect. It is a reccuring theme in most of the post in this forum that give truthful feedback about MPG, I expect 2012 JK to be NO different. I expect you will get nearly 20 MPG in factory form fully broken in but when you start modding you will see the MPG hits as I have detailed. I have experienced the same with my 2008 JK "X" that gets 16 MPG running a 3" lift, 35" BFG's, Gibson exhaust, VIPER Throttle Body, Hypertech "REGULAR" tune with extra weight (see profile). I commute 500 miles weekly.

https://www.jk-forum.com/forums/show...63#post2702663

 

48 Miles lost per tank just from a lift? ... somethin else is wrong here. sounds like a change in driving habits or possibly poor fuel?

Are you going by the comp? DO NOT go by that horrid excuse for a calculator. You will see it tick off avg mpg's when in park @ idle. It takes what is going on NOW and doing an average over miles. Coasting down a 5 mile hill and coasting down a 100 mile hill and then driving like an absolute ass foot to the floor exactly in the same mannor for 1 mile after each hill will net different results.

Do your math by hand. .... 3 tanks worth and i bet you find your mileage again