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Unread 08-10-2012, 10:10 PM   #16
xj_noob
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2001 XJ Cherokee 
 
Join Date: Dec 2011
Location: round lake park, illinois
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3inch lift on 29 inch Firestone Destination A/T tires.

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Unread 08-10-2012, 10:14 PM   #17
DoctorTim
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im runnin 3.5" with 31" mud tires. my mpg will be considerably less than yours.
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Unread 08-10-2012, 10:18 PM   #18
DerMeister
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Quote:
Originally Posted by xj_noob

It sure does help me out. :/ I just put it in my gas tank to clean my injectors and I get 320~ miles to the tank.
Thats not very good. Miles per tank is also a very poor indicator of mpg.

No driving conditions or mods are listed, but thats average at best.
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Unread 08-10-2012, 10:23 PM   #19
xj_noob
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Okay well other than the lift and the tires, I have a spectre air filter in the stock air box and the magnaflow exhaust mentioned earlier. I average about 18-19 mpg. Which I am fairly happy with lol.
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Unread 08-10-2012, 10:26 PM   #20
xj_noob
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Quote:
Originally Posted by XJ-Tim
im runnin 3.5" with 31" mud tires. my mpg will be considerably less than yours.
Yeah the mudders were your death sentence lol. Nevertheless, you still have some bad*** tires.
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Unread 08-10-2012, 10:29 PM   #21
DerMeister
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Quote:
Originally Posted by xj_noob View Post
Okay well other than the lift and the tires, I have a spectre air filter in the stock air box and the magnaflow exhaust mentioned earlier. I average about 18-19 mpg. Which I am fairly happy with lol.
Do yourself a favor, and remove the emblem from your spectre filter. Mine came off and got sucked into the throttle body lodging it open at 70 mph.

18-19mpg isn't too bad, but your tank is 20 gallons so 320 miles to a tank(20 gallons) is only 16 mpg. See what I mean?
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Unread 08-10-2012, 10:43 PM   #22
xj_noob
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Good call friend, I'll hop to it in the morning.
Odd thing is, when i top off, I can only fill up about 17 gallons and the needle goes past the "F" :/ and i did in fact read somewhere that my tank is supposed to hold 20 gallons, like you said.
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Unread 08-10-2012, 10:59 PM   #23
Reptile
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You're not gona get great mileage with that size of tires to begin with. Increased tire size creates more friction. I found that coolant temp sensor can considerably affect mileage, if it is bad. Another think you should be checking is your battery cables, ground, and distributor. Make sure they are all free of corrosion, very important. Consider replacing the spark plug wiring as well. Other factors such as summer heat and the way you drive can also negatively affect mileage. I'm with Azzy on the additives, they seldomly make a difference; there is no magical cure.
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Unread 08-10-2012, 11:56 PM   #24
DerMeister
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Quote:
Originally Posted by Reptile
Other factors such as summer heat and the way you drive can also negatively affect mileage.
Unless youre referring to the use of AC, how does summer heat negativley affect mileage? The general notion is that it is better for mileage for several reasons.
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Unread 08-11-2012, 06:17 AM   #25
Richie09
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gearing

I don't think going to 4.10 is going to help...engine will run at higher rpm for any given speed, more power in other words.
Seafoam works. I don't remember the ingredients name but it is the same used by MoPar for removing carbon buildup on valves and rings, also does keep the injectors clean and removes moisture in the tank. Putting a pint in the full tank once a year is regular practice here with both our cars, buy by the gallon keeps it down to about $6.50/year for a car.
For whatever its worth I am running stock allterrain and getting 19 mpg with no highway miles.
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Unread 08-11-2012, 06:32 AM   #26
xj_noob
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Try a new fuel pump and while youre at it clean all the gunk and debris from your tank.
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Unread 08-11-2012, 07:05 AM   #27
escapeartist
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?
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Unread 08-11-2012, 11:24 AM   #28
david92xj
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Quote:
Originally Posted by DerMeister View Post
Unless youre referring to the use of AC, how does summer heat negativley affect mileage? The general notion is that it is better for mileage for several reasons.
a/c or not, wont make that big of a difference
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Unread 08-11-2012, 01:15 PM   #29
jjshbetz11
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Drive like there's a egg between the skinny pedal and foot. Draft semi's whenever possible, pizza cutter tires, little higher than normal tire pressure, open element air filter, new plugs, no muffler, and reset PCM. Don't know the mileage I get but I travel a hundred miles a day 5 to six days a week. A full tank on Monday morning gets me to Thursday. I have to refill on Friday. That's roughly 400 miles to the tank.

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Unread 08-11-2012, 01:16 PM   #30
jjshbetz11
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Quote:
Originally Posted by jjshbetz11
Drive like there's a egg between the skinny pedal and foot. Draft semi's whenever possible, pizza cutter tires, little higher than normal tire pressure, open element air filter, new plugs, no muffler, and reset PCM. Don't know the mileage I get but I travel a hundred miles a day 5 to six days a week. A full tank on Monday morning gets me to Thursday. I have to refill on Friday. That's roughly 400 miles to the tank. Oh and keep it under 2k rpm

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