I have searched and read numerous posts about mpg but most posts did not answer the question of how many mpg were actually lost with a given lift / wheel combo. Most posts simply stated something like I'm getting 14 mpg with 35s and a 3" lift. This does not help because some threads reveal that dfferent drivers get different mpgs even on bone stock rigs (because of driving mostly in traffic, mostly at the speed limit, pushing the brick like aero regularly on a highway commute at 70 mph or having a lead foot when leaving lights etc).
What would be useful is how much did you get with your stock Jeep vs how much you got after a lift. Then, assuming the driving style remained about the same, we would know that x lift with x wheels is likely to cause a loss of x mpg.
I already know I didn't buy a Prius (so please forget those comments). I am trying to decide whether to go with lightweight aluminum bumpers and no lift or do a modest 2" lift, heavier steel bumpers and eventually move to 33s. Since it looks like I am doing > 15,000 miles a year, gas mileage is part of the equation and I would like to know what I'm getting into. I'm getting 20-21 mpg in a stock 2012 Rubicon with manual trans. If I were to modify the Jeep so it only got 14 mpg I would be pretty unhappy.
So - if you feel like helping me (and others following) learn, please post your original stock mpg, your lift and wheel/tire size and your mpg since so we have a before and after from the same driver. Many thanks!
When it was stock last summer, I'd crack 20 mpg on a good day, once I saw 22 indicated in EVIC, but overall, I was about 19 mpg driving relatively conservatively. At present, I'm waiting for similar conditions to roll back around in another month or so to make a comparison.
However, of late, I see usually 18-18.5 mpg if I drive conservatively and down shift when I hit hills. That's commuting over hills most days, traveling on highways, some stop and go mixed in - I never seem to find that happy place where I trundle along at 55 mph all day long. =)
You can check my profile for specifics, but I'm still on stock rubber with ~3 inches of lift. I'm actually interested to see how my fuel economy will change with new tires. I wish I could mount up 4-5 different sets and drive a test loop under reasonably well controlled conditions and work up some numbers. Ultimately, though, I doubt I'll be able to convince myself to sacrifice traction of the non-pavement variety. I've been stuck, I've seen folks stuck - I'd rather do the latter.
See this is not an easy question to answer ... If you are staying with your factory gear set when you can expect to lose 1-3 MPG going from a 29in tire to a 33 .. However you have a rubicon . If im not mistaken then you have 31-32 in tires from the factory so going to a 33 will not change much .. But when you add weight it can kill your mpg .. If you are that worried about the mpg then i would look into some performance parts to go with the kit .. Like a programmer (to set your tire size and get your trans to shift when it should , also it will tell your ecm to change the shift points and lower the rpm when on the hwy .. ) You can also add a free flowing air filter and exhaust (cat back) to get you 2-4 mpg back .. So its all up to you , weight and bigger meets will drop mpg ..
Before 33s and 2.5 lift - avg 20-21mpg
After - avg 17mpg
Most of what was been posted tires & lift is true. Bigger tires tend to be heavier and will affect city mileage. A lift will increase aerodynamic drag and impact highway mileage. I've got an 04 Crossfire that only has 215 hp but it gets 25 mpg and will do 160MPH (yes I pegged the speedo...once) due to the gearing & the aerodynamics of the vehicle.
The Jeep is a brick in terms of air resistance, anyone getting 25+mpg is driving downhill both ways
I'm planning to add steel bumpers front/rear. I'm hoping a 4.10 gear upgrade in the manual will give me 6th gear back on the highway and keep me at least around 17mpg.
2008 Sahara Unlimited 3.73 gears highway all stock 22-23mpg.
After 3.5" lift and 35" Pitbulls, Superchips programmer again 90% highway 17-18 mpg
__________________ Jeff _(OIIIO)_
08 Black and Khaki JK Sahara Unlimited, Dual Tops, MyGig, Tow pkg, Trax-Lok Rear Diff,
Mods -- 3.5" Rock Krawler front springs, 2.5 TerraFlex BB, PitBull Rockers 37x12.50x17 on ProComp 7069 alloys, AEV Premium Bumper,
Hmmm 2008 JKUR 6spd bone stock. Can't figure out why I'm getting 12.5 mpg on average (counted at the pump and on the odo... Real numbers). Want to lift and tires but scared it'll grind down to a standstill.