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I just went on my first road trip with the Rubi. When I first got the Rubi I was a little concerned when I was lucky to get 200 miles before the low fuel light came on. I contributed this to a new engine and figured the mileage would get better as the engine broke in. I've got over 2000 miles on the Rubi and the MPG has not increased by much. My factory sticker states the Rubi with the 4.0 and auto should get 16 city / 19 highway. I'm not getting anywhere close to this. Right now I get about 13 city and 15 highway. My last road trip I averaged 15 mpg and was driving 65-70 mph with the air on and the hard top on. I'm still set up stock. So I figure I should get somewhere near factory specs for mileage. Is this false advertising???

After reading numerous posts about gas mileage I know this is common. I know I shouldn't be complaining because I do have a jeep and so many other unfortunate people out there have to drive around in there typical gas sipping 2 wheel drive cars. And most people would say why would I buy a jeep or 4x4 if I was worried about gas mileage. It's not that I'm too concerned about gas mileage but come on, when my friend with a Ford Excursion weighing in at 8900 lbs with a V-10 gets better gas mileage city and highway than my 4600 lbs jeep with a 6 cyl... it makes me wonder if there something wrong.

Anyway just had to vent. The real question is what type of gas mileage are you getting with your setup. I'm looking to upgrade to 5" lift and 35" tires but I can only imagine what would happen to my gas mileage then. At least then there will be a reason for getting crappy mileage.

How much difference is there in MPG from 31 - 33 - 35?

Thanks for listening.
 

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what tire pressure for road trips?

my avg is around 13.5 mpg in the city...15 highway

i got 16.5 mpg last fri and i aired up to 35psi ....
normally i run 28 on the paved roads and 15 offroad.

i have 33'' tires

mac
 
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Discussion Starter #4
I run 35"'s and seem to get right around 13mph... I am considering doing a TB spacer in the futer, better exaust ect..ect.. It seems these help alot.
 

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My first trip from WA to CA the Rubi had less than 1000 miles on it and I started out getting 13 -14 mpg on my way back I was getting 16 - 17 mpg, I have about 16,000 miles on it now and am getting 19 mpg when I drive between 65 - 70 if I drive 70 - 80 it drops to about 16 mpg.
I am still running the stock tires at about 40 psi.
 
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Discussion Starter #6
My last trip I took we went 240 miles each way. On the way there I drove 75-80 mph with the a/c on and averaged 15.4 mpg. On the way back at 65 mph, a/c off, and averaged 15.9. The terrain flat and wind was minimal. My last 6 tanks of gas were mixed city highway driving and averaged 14 mpg. As I said before it wouldn’t bother me so much except that my jeep is stock and the sticker on it says 16 city / 19 highway.

I took the Rubi in to the dealership because of the gas mileage problem and they said they could probably reset the computer which might help…I also told them the tail pipe had a lot of black soot on it, which I thought indicated running rich. The engine is also making a ticking sound. It sounds like a lifter or valve. It’s definitely coming from the engine as the frequency of the tick increases with engine RPM.

I made him get in the jeep and close the doors and listen to it, to confirm that there was indeed a ticking noise coming from the engine and that it wasn’t part of my imagination or normal operation. He said it sounded like the purge valve opening which was normal… I told him if he could take me to any other wrangler on the lot and they all made the same noise I would believe him. My jeep didn’t do that when I first got it and my last TJ didn’t make that sound either.

I’ll keep you all up to date on the diagnosis when I get it back tomorrow. I just have a feeling that they’ll tell me it’s normal operation.
 
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Well latest update, just as I had feared. The dealer called me up and said they couldn’t find anything wrong. :x

-The mileage problem: No problems. The computer was good so they topped off my tank and drove it 71 highway miles. Filled it back up and they got 16.9 mpg. Still not the 19 mpg the sticker advertises. He was probably driving it 55 mph. :twisted:

-Ticking sound coming from the engine: Also normal. The engine guy couldn’t hear anything out of the norm. He couldn’t hear the ticking noise. Said they would look at it again tomorrow when the engine is cold. I can hear it all the time… :x

I guess I’ll take it to the dealer where I bought it and see if they come up with the same thing. I just want to get all this little stuff fixed before I put my mods on so they can’t blame everything on a lift and bigger tires.
 

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2Can said:
Well latest update, just as I had feared. The dealer called me up and said they couldn’t find anything wrong. :x

-The mileage problem: No problems. The computer was good so they topped off my tank and drove it 71 highway miles. Filled it back up and they got 16.9 mpg. Still not the 19 mpg the sticker advertises. He was probably driving it 55 mph. :twisted:

-Ticking sound coming from the engine: Also normal. The engine guy couldn’t hear anything out of the norm. He couldn’t hear the ticking noise. Said they would look at it again tomorrow when the engine is cold. I can hear it all the time… :x

I guess I’ll take it to the dealer where I bought it and see if they come up with the same thing. I just want to get all this little stuff fixed before I put my mods on so they can’t blame everything on a lift and bigger tires.
Hey the ticking sound is normal, so is the clutch rattley sound after you turn it off and all the other crazy jeep noises.
Pete M
 
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Discussion Starter #10
I'm still averaging 16.2 and that is mostly in the city driving. Longest freeway is about 15 miles ever so often. Ride hight didn't matter.

Ron
 

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2can, I believe that noise is normal but I'd like to know what they have to say. As far as gas mileage goes if you regear as you go up in size your gas mileage should stay the same or get better depending on how you regear. Don't know for an auto, but for a manual I ran 4.56 gearing and 33's and got better gas mileage than stock. My Rubi's manual (it's still stock) and it gets about 240 miles on 16.5 gallons (average).
 

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Man, if I can get anything better than 180 miles per tank I'll be happy. I have a TB spacer coming in today that I may see if it helps my mileage. Otherwise I need to find out whats wrong.
 

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2Can said:
-Ticking sound coming from the engine: Also normal. The engine guy couldn’t hear anything out of the norm. He couldn’t hear the ticking noise. Said they would look at it again tomorrow when the engine is cold. I can hear it all the time… :x
Jimmy,
Next time you are hear that ticking noise, try turning off your vent fan. I always (both this Jeep and the last) hear a slight tick coming from the fan.
 

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Jimmy....The ticking noise is normal... I am getting around 15mpg average with 35's...How many miles you have on the JP?
 

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LILRDJP said:
Jimmy....The ticking noise is normal... I am getting around 15mpg average with 35's...How many miles you have on the JP?
I now see that you have 2000....give it somemore time...
 

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Quit complaining :wink: I get 8 to 10 in town. 12-14 hwy if I take it slow. :mad:
33" tires

I would imagine that the mileage ratings are taken at 55 MPH as that speed will get about the best mileage.

Brian
 

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Finally fed up with my mileage I put a poweraid TB spacer on last night. Now, after reading anything and everything I can on TB's I didn't think I'd notice much if anything, but there's a definately seat of the pants push now that wasn't there before. I also appear to be a hundred or so rpm lower cruising at 45mph.
 
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Discussion Starter #18
Rubicon MPG

Hello... I nromally get about 15-15.5 when driving they way I like to drive and around 18-18.5 driving easy (i.e. keeping my foot out of it, but driving whatever speed I want). My "fuel warning" normally pops up around 260 miles. I always check the the mileage on fuel required to "fill the tank"
 
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