gas - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > TJ Jeep Wrangler Forum > TJ General Discussion Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 12-12-2007, 09:18 AM   #1
Member
 
Join Date: May 2007
Location: where my hat is
Posts: 1,489
gas

Dumb question but - 89 octane gas is ok in the 4.0 I6. Engine right?

Anyone use anything else for any reason?

Smeghead is offline   Quote Quick Reply
Old 12-12-2007, 09:43 AM   #2
Jeeper
 
sgnellett's Avatar
 
Join Date: Aug 2007
Location: Under a sheet of ice, you know, from Global Warming!
Posts: 2,949
Quote:
Originally Posted by Smeghead View Post
Dumb question but - 89 octane gas is ok in the 4.0 I6. Engine right?

Anyone use anything else for any reason?
I like to run a tank of rocket fuel thru it once a month or so, keeps the flux capacitor spinning smoothly and keeps the muffler bearings correctly oriented on the left hand threaded blinker fluid reservoir! I did have to upgrade to the unobtainium fuel lines though...







Seriously, 87 is all I ever run in Lucy, and she's ok with that!

__________________
SGNellett, 02 TJ "LUCY" 3" BDS w/ quick disco's, 33x12.5x15's on Chrome Steel Tailgunners, K&N CAI, Tomkens front & rear w/ swing away tire carrier

Quote:
Originally Posted by skeeter View Post
And the most important safety, I never put my booger hook on the bang switch unless I'm ready to fire.
sgnellett is offline   Quote Quick Reply
Old 12-12-2007, 09:47 AM   #3
Jeeper
 
98TJ's Avatar
 
Join Date: Oct 2007
Location: Vestal
Posts: 127
I actually do run a tank of premium through it about once a month. I run a fuel system cleaner through it at every oil change, and i run synthetic oil so she runs like she's brand new.
98TJ is offline   Quote Quick Reply
Old 12-12-2007, 10:00 AM   #4
MCG
Jeeper
 
MCG's Avatar
 
Join Date: May 2007
Location: Tampa
Posts: 541
I used to use premium in the Jeep, but, since the fuel prizes going up I decided to use the cheap one and no problem at all, it also feels more strong it’s just me but no problems at all.
A fuel injector cleaner once a year and a body throttle cleaning in each tune up it might work.
Its matter of good maintenance.
MCG is offline   Quote Quick Reply
Old 12-12-2007, 11:08 AM   #5
Jeeper
 
richp's Avatar
 
Join Date: Mar 2007
Location: Pocono mountains
Posts: 1,559
Use the cheapest gas you can find, then every 3,000-5,000mi stick a 20oz bottle of Chevron Techron FUEL SYSTEM CLEANER not FI cleaner.
richp is offline   Quote Quick Reply
Old 12-12-2007, 12:13 PM   #6
MOz
Jeeper
 
MOz's Avatar
 
Join Date: Apr 2007
Location: Poconos
Posts: 2,484
The user manual states we should run 87 octane and that anything higher can damage the engine.

I follow something close to richp. I run the cheapest gas I can find and once a month throw in a bottle of STP fuel injection cleaner to get rid of the excess moisture.
__________________


It ain't no fun unless you get some of it on you.
MOz is offline   Quote Quick Reply
Old 12-12-2007, 12:36 PM   #7
Jeeper
 
Walkeraviator's Avatar
 
Join Date: Jul 2007
Posts: 1,084
1. 87 octane is 100% ok. Higher octanes are for hiigher compression. They prevent predetonation from increasing temperatures as gas is compressed. This is why they now allow some airplanes (with STCs) to run on car gas while bigger engines still use 100 Octane. So in short, unless you have a turbo on your 2.5 or high compression head and pistons in your 4.0, 87 octane is good to go all the time.

2. Fuel system cleaners are basically concentrated detergents that are already found in the gas you buy at the pump. So you dont have to do it, but it sure cant hurt.

3. Oil additives like Slick 50 is a great idea if you run conventional oil about every 3 oil changes. I know Slick 50 works wonders... i even saw an airplane mechanic (illegaly) put slick 50 in an IO-520 (airplane engine) once. It stopped all il usage in that motor which is a big deal considering it is a six cylinder volkswagen motor with 520c.i. displacement. Or you could just use synthetic all the time.
Walkeraviator is offline   Quote Quick Reply
Old 12-12-2007, 01:00 PM   #8
Jeeper
 
nicosuave's Avatar
 
Join Date: Oct 2007
Location: twin cities suburb, mn.
Posts: 99
Richp what's the differance between the chevron system and FI cleaner? I've always heard the fuel system cleaner is for carbed engines?
nicosuave is offline   Quote Quick Reply
Old 12-12-2007, 01:45 PM   #9
Jeeper
 
richp's Avatar
 
Join Date: Mar 2007
Location: Pocono mountains
Posts: 1,559
Quote:
Originally Posted by nicosuave View Post
Richp what's the differance between the chevron system and FI cleaner? I've always heard the fuel system cleaner is for carbed engines?
I've been told the FI cleaner is a different mix of stuff made to break down the crud that builds up in the IF bores which I was also told is a specific 'stuff' vs the normal build up that gas leaves in the entire fuel system. I just know that I tried both and the FI cleaner did not seem to do anything, the fuel system cleaner did. The FI cleaner is also cheaper so it may not have the higher concentrations of whatever the solvents and cleaners are.
I have also heard Acetone is a good cleaner and improves mileage but I've not tried it.
richp is offline   Quote Quick Reply
Old 12-12-2007, 02:14 PM   #10
Jeeper
 
parrot head's Avatar
 
Join Date: Jul 2007
Location: Connecticut
Posts: 406
Quote:
Originally Posted by Walkeraviator View Post
1. 87 octane is 100% ok. Higher octanes are for hiigher compression. They prevent predetonation from increasing temperatures as gas is compressed. This is why they now allow some airplanes (with STCs) to run on car gas while bigger engines still use 100 Octane. So in short, unless you have a turbo on your 2.5 or high compression head and pistons in your 4.0, 87 octane is good to go all the time.

2. Fuel system cleaners are basically concentrated detergents that are already found in the gas you buy at the pump. So you dont have to do it, but it sure cant hurt.
X2
So many people incorrectly believe that higher octane = more power, and it is so untrue. Higher octane just allows you to run a higher compression ratio or more timing advance without pre-ignition (pinging)
__________________
“He who knows not and knows not that he knows not, he is a fool, shun him.
He who knows not and knows he knows not, he is simple, teach him.
He who knows and knows not he knows, he is asleep, wake him.
But he who knows, and knows he knows, he is wise, follow him.”


89 yj 4 banger 5sp. 2" BL 31x10.50 fixed up and sold
97 tj 4.0 Auto 4"RC lift 33x12.50 mud rovers on outlaw IIs . Smitty bumpers
parrot head is offline   Quote Quick Reply
Old 12-12-2007, 03:54 PM   #11
MoA
Jeeper
 
MoA's Avatar
 
Join Date: Apr 2007
Location: kokomo indiana
Posts: 2,927
x2 on the fuel cleaner stuff.. i run it in my jeep like every 3 fill-ups.. been doing it for the last 6 months or so.. use to do it like every 10.. i went from like 12 mpg back to 14-15 like it was before i put on the 33s..

my jeep also loves heat in the winter.. wont start without some of it in the tank for some reason? still havent found a leak in the tank.. but somehow water is getting in there
__________________
99 sahara :: 2'' coils (front), jks acos f&r, jks front trackbar, jks bl/mml, RE monotube shocks, hp30/d44, 33'' procomp mts, 15x8 eagle alloy 187s, hella optilux fogs, raingler nets, & more random junk::

06 charger r/t :: 5.7l hemi w/ flipstick, tinted windows, leather heated seats, 2 kenwood 12s =D my new baby ::
MoA is offline   Quote Quick Reply
Old 12-12-2007, 05:03 PM   #12
Drives by Braille

WF Supporting Member
 
AzTJ's Avatar
 
Join Date: Dec 2006
Location: For-8-Oh!
Posts: 13,629
Jeeps live long on the cheap stuff. When you start doing the routine maintenance on them, you see the big price difference between it and your WRX.
AzTJ is offline   Quote Quick Reply
Old 12-13-2007, 07:58 AM   #13
MOz
Jeeper
 
MOz's Avatar
 
Join Date: Apr 2007
Location: Poconos
Posts: 2,484
Quote:
Originally Posted by MoA View Post
x2 on the fuel cleaner stuff.. i run it in my jeep like every 3 fill-ups.. been doing it for the last 6 months or so.. use to do it like every 10.. i went from like 12 mpg back to 14-15 like it was before i put on the 33s..

my jeep also loves heat in the winter.. wont start without some of it in the tank for some reason? still havent found a leak in the tank.. but somehow water is getting in there
If you are still getting moisture in your gas, try changing stations for a while.
__________________


It ain't no fun unless you get some of it on you.
MOz is offline   Quote Quick Reply
Old 12-14-2007, 06:21 AM   #14
Jeeper
 
parrot head's Avatar
 
Join Date: Jul 2007
Location: Connecticut
Posts: 406
Quote:
Originally Posted by MOz View Post
If you are still getting moisture in your gas, try changing stations for a while.
X2 The source of the moisute could be the source of your gas
__________________
“He who knows not and knows not that he knows not, he is a fool, shun him.
He who knows not and knows he knows not, he is simple, teach him.
He who knows and knows not he knows, he is asleep, wake him.
But he who knows, and knows he knows, he is wise, follow him.”


89 yj 4 banger 5sp. 2" BL 31x10.50 fixed up and sold
97 tj 4.0 Auto 4"RC lift 33x12.50 mud rovers on outlaw IIs . Smitty bumpers
parrot head is offline   Quote Quick Reply
Old 12-14-2007, 07:19 AM   #15
Member
 
Join Date: May 2007
Location: where my hat is
Posts: 1,489
Quote:
Originally Posted by AzTJ View Post
Jeeps live long on the cheap stuff. When you start doing the routine maintenance on them, you see the big price difference between it and your WRX.
Yeah my WRX ran on 93OCT only. And the custom tune was done with 93oct+a little octane booster, so I was kinda stuck in that rut. Crappy gas even crappy 93OCT gas really affected it quite drastically.
I ran with 1/8 gallon of 100 OCT race gas at the track too, THAT sheet is expensive.

It was nice to fill up with sub-$3 gas on my trip home. Even though the jeep is much worse on gas than the Suby, paying $3.44 a gallon really sucked.
I also learnt that with this Jeep, you can put TONS more gas in after the first 'click' of the pump. Not something I could do before. The 'click-stop' meant it really was full.
Smeghead is offline   Quote Quick Reply
Old 12-14-2007, 03:23 PM   #16
Jeeper
 
machine's Avatar
 
Join Date: Aug 2007
Location: lajes field, terceira, azores
Posts: 93
Send a message via Yahoo to machine
4 banger, and all i run is 93oct!






but thats because all they carry on base is premium. and its usually between $3.20 - $3.50 a gal. sweet indeed. i could go off base, but then id have to pay 1,50+ euro per liter.

machine is offline   Quote Quick Reply
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Jeep Wrangler Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Download our Mobile App

» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 03:08 AM.



Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC