stock and mileage? - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > General Jeep Discussions > Tires & Wheels

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 08-21-2011, 03:29 PM
Thread Starter
  #1
Jeeper
 
seanpsills's Avatar
 
Join Date: Jun 2011
Location: Hawkinsville, GA
Posts: 39
stock and mileage?

I am currently running 31x10.50. Will switching back to stock rims and tires drastically improve my gas mileage on my 97 2.4L wrangler? It is an automatic and I never drive over 55mph and its my daily driver.

seanpsills is offline   Quote
Old 08-21-2011, 05:50 PM   #2
Jeeper
 
eddsox's Avatar
 
Join Date: Aug 2011
Posts: 30
I don't know about drastic improvements. Running stock size tires will improve mpg. No Jeeps get great millage and the 3sp auto doesn't help. The 97-02 came with the 2.5 the 03-06 were 2.4. You can re-gear your axles to get some of the power and millage back, but nothing is going to make it great on gas.

eddsox is offline   Quote
Old 08-21-2011, 09:24 PM
Thread Starter
  #3
Jeeper
 
seanpsills's Avatar
 
Join Date: Jun 2011
Location: Hawkinsville, GA
Posts: 39
when you say regear my axles please explain. I am pretty new at all of this.
seanpsills is offline   Quote
Sponsored Links
Advertisement
 
Old 08-22-2011, 06:53 PM   #4
Jeeper
 
eddsox's Avatar
 
Join Date: Aug 2011
Posts: 30
Your Jeep came from the factory with 3.73 gears in the axles. This was set from the factory for the stock tires. When you increase tire size you need to increase axle gearing as well. With most vehicles you can go up a couple of tires sizes without re-gearing. When you go up more than that you loose power and mpg. It is fairly expensive to have axles re-geared but will bring power and millage back. If millage is main concern I would run stock size tires. If you want the 31s gearing is your best bet.
eddsox is offline   Quote
Old 08-22-2011, 07:52 PM
Thread Starter
  #5
Jeeper
 
seanpsills's Avatar
 
Join Date: Jun 2011
Location: Hawkinsville, GA
Posts: 39
I really appreciate the info. What size are stock tires and rims for my 97?
seanpsills is offline   Quote
Old 08-23-2011, 06:15 PM   #6
Jeeper
 
eddsox's Avatar
 
Join Date: Aug 2011
Posts: 30
Most likely 205x75x15 It should say on the sticker on inside of drivers door. If it is still there. If you don't re-gear 225s or 235s would still help millage 205s will look really small. I
eddsox is offline   Quote
Old 08-23-2011, 08:15 PM   #7
Jeeper
 
AmericaOverland's Avatar
 
Join Date: May 2011
Location: Edna, TX
Posts: 693
Quote:
Originally Posted by eddsox View Post
Most likely 205x75x15 It should say on the sticker on inside of drivers door. If it is still there.
Actually, the label is on the body, below the door frame on the inside side, just ahead of the driver's seat. I didn't want him taking the door panel off to find it.

The TJ stock size seems to be 30X9.5
__________________
2005 Jeep Wrangler Unlimited (LJ), silver w/black top, auto, 4WD - Tow Truck

2006 Forest River Surveyor SV160T hybrid travel trailer
AmericaOverland is offline   Quote
Old 08-24-2011, 05:42 PM   #8
Jeeper
 
eddsox's Avatar
 
Join Date: Aug 2011
Posts: 30
30x9.5 were never a option for the 2.5 4cyl. They were a option for the 4.0 with 3.73 gears. Most TJs 4cyl and 6 didnt come with 30s
eddsox is offline   Quote
Old 08-24-2011, 05:57 PM   #9
Jeeper
 
AmericaOverland's Avatar
 
Join Date: May 2011
Location: Edna, TX
Posts: 693
Quote:
Originally Posted by eddsox View Post
30x9.5 were never a option for the 2.5 4cyl. They were a option for the 4.0 with 3.73 gears. Most TJs 4cyl and 6 didnt come with 30s
If they were an "option" for the 4.0, then what did they come with in stock size? My tire pressure label states that size as the "original" size (which is the word used on the label, "original"). I'm curious to find out as to why my gas mileage is down. I haven't run through my tank yet, but it seems to be running down faster than I thought, even factoring in city driving and posted city/hwy mileage estimates.

Could it be that the mileage estimates I want are really for the TJ standard and not the Unlimited version, which is heavier?
__________________
2005 Jeep Wrangler Unlimited (LJ), silver w/black top, auto, 4WD - Tow Truck

2006 Forest River Surveyor SV160T hybrid travel trailer
AmericaOverland is offline   Quote
Old 08-24-2011, 06:09 PM   #10
Jeeper
 
Join Date: Sep 2010
Posts: 790
Quote:
Originally Posted by AmericaOverland View Post
If they were an "option" for the 4.0, then what did they come with in stock size? My tire pressure label states that size as the "original" size (which is the word used on the label, "original"). I'm curious to find out as to why my gas mileage is down. I haven't run through my tank yet, but it seems to be running down faster than I thought, even factoring in city driving and posted city/hwy mileage estimates.

Could it be that the mileage estimates I want are really for the TJ standard and not the Unlimited version, which is heavier?
The LJ standard tire size was 30X9.5 The Rubicon would come with 16" wheels and 31's. Gas gauge is worthless in determining mileage. Gotta actually calculate what you are getting. My gauge reads empty when I'm at about 15 gallons...which means I still have tons in the tank (4 or 5 gallons...can't remember exactly which).
Bubba68CS is offline   Quote
Old 08-24-2011, 06:18 PM   #11
Hardcore Jeeper
 
Peepers's Avatar
 
Join Date: Oct 2010
Location: Windsor, CT
Posts: 3,320
I believe stock size on my 98 was 215/75r15 or 225/75r15
__________________
What have we got?
We have one heavily armed Recreational Vehicle


ΣΧ
The Power Tech 6
Peepers is offline   Quote
Old 08-24-2011, 07:13 PM   #12
Jeeper
 
AmericaOverland's Avatar
 
Join Date: May 2011
Location: Edna, TX
Posts: 693
Quote:
Originally Posted by Peepers View Post
I believe stock size on my 98 was 215/75r15 or 225/75r15
I don't know what that means. I don't have a converter handy to understand in inches what that means.

As for the gas gauge, because I am on a budget for the remainder of this month, I have not done a complete refill and run it down. However, I did put over 11 gallons in it and I'm waiting for the first time the light comes on. I will be taking a trip soon, and at that time I can do the refills and measure my mileage.
__________________
2005 Jeep Wrangler Unlimited (LJ), silver w/black top, auto, 4WD - Tow Truck

2006 Forest River Surveyor SV160T hybrid travel trailer
AmericaOverland is offline   Quote
Old 08-25-2011, 05:02 PM   #13
Jeeper
 
eddsox's Avatar
 
Join Date: Aug 2011
Posts: 30
225s are28 inch tall tires. The LJs all had 30s with 3.73 gears. What is funny about the factory listed MPGs, is they pretty much all say 15city 19hway regardless of tire size, gearing, TJ or LJ. I was recently looking at JKs at the dealer. Every Wrangler, 4dr, 2dr, auto or stick all said 16city 19highway.
eddsox is offline   Quote
Old 08-25-2011, 06:25 PM   #14
Jeeper
 
AmericaOverland's Avatar
 
Join Date: May 2011
Location: Edna, TX
Posts: 693
Quote:
Originally Posted by eddsox View Post
225s are28 inch tall tires. The LJs all had 30s with 3.73 gears. What is funny about the factory listed MPGs, is they pretty much all say 15city 19hway regardless of tire size, gearing, TJ or LJ. I was recently looking at JKs at the dealer. Every Wrangler, 4dr, 2dr, auto or stick all said 16city 19highway.

Oh... Owww!! I guess I better double my gasoline budget. Historically, my budget has been only $60 a month. So it's not like I'm going from $200 a month to $400 a month. I'd be breaking my lease before that happens (if I found another job paying the same, but much further away).
__________________
2005 Jeep Wrangler Unlimited (LJ), silver w/black top, auto, 4WD - Tow Truck

2006 Forest River Surveyor SV160T hybrid travel trailer
AmericaOverland is offline   Quote
Old 08-26-2011, 12:12 PM
Thread Starter
  #15
Jeeper
 
seanpsills's Avatar
 
Join Date: Jun 2011
Location: Hawkinsville, GA
Posts: 39
My sticker shows 205x75x15 for stock but my 31x10.5 are killing my mpg and power I believe. what size tire would you guys recommend but I want to stay with an aggressive A/T tire. If I wanted to stay with my 31x10.5 and re-gear what do you recommend and approximately how much would it cost me to re-gear?
seanpsills is offline   Quote
Old 08-26-2011, 12:22 PM   #16
Rock-Rubber

WF Supporting Member
 
GoldenSahara00's Avatar
 
Join Date: Aug 2010
Location: Central PA
Posts: 16,970
1200 bucks to regear and its not worth it IMO. get smaller tires or a bigger wallet.

What kind of mpgs are you getting that are so bad?
__________________
Ryan - A good eye, a light foot, and a smart rig.
Bolt-ons are boring
AMERICAN JEEPER
My Build - https://www.wranglerforum.com/f118/pr...a00-74622.html
Rausch Creek Trip: 2014 Trip Coming Soon
GoldenSahara00 is offline   Quote
Old 08-26-2011, 12:53 PM
Thread Starter
  #17
Jeeper
 
seanpsills's Avatar
 
Join Date: Jun 2011
Location: Hawkinsville, GA
Posts: 39
going to check my mileage this afternoon when I go to the pump. Definitely not spending 1200 to re-gear. What size tire would you recommend?
seanpsills is offline   Quote
Old 08-26-2011, 01:29 PM   #18
Rock-Rubber

WF Supporting Member
 
GoldenSahara00's Avatar
 
Join Date: Aug 2010
Location: Central PA
Posts: 16,970
between 225 and 245.

honestly I doubt your mpgs are that bad, it is more than likely in your head.

I run 33 inch tires on the worst possible gearing you get have - 3.07, with a 3spd auto. albeit its a 4.0, but still. I get 14-15 town and up to and sometimes over 17 hwy.
__________________
Ryan - A good eye, a light foot, and a smart rig.
Bolt-ons are boring
AMERICAN JEEPER
My Build - https://www.wranglerforum.com/f118/pr...a00-74622.html
Rausch Creek Trip: 2014 Trip Coming Soon
GoldenSahara00 is offline   Quote
Old 08-27-2011, 06:08 PM   #19
Jeeper
 
eddsox's Avatar
 
Join Date: Aug 2011
Posts: 30
I would look for a good set of used 225s or 235s. Since so many guys go up in tire size, you can find some good deals. Try any local 4x4 shops,local classifieds etc.
eddsox is offline   Quote
Old 08-27-2011, 09:13 PM   #20
Jeeper
 
computeruser's Avatar
 
Join Date: May 2010
Location: East Lansing, MI
Posts: 811
Quote:
Originally Posted by AmericaOverland View Post
I don't know what that means. I don't have a converter handy to understand in inches what that means.
Google? Anybody?

You're probably not going to see a huge improvement going from 31 to 28" tires, honestly, because most of the fuel economy penalty is coming via aerodynamics, not tire height/gearing issues.

I've got a 3spd auto, 3.73 gears, and 31" tires with a 4.0L and get 12/14mpg unladen. Lifetime best was 15.9mpg on an entire tank at 55mph, no stopping. Even if I could bump it up to 14/16 or 14/18, would it really make any material difference to my wallet at the pump? I don't think so.
computeruser is offline   Quote
Old 08-27-2011, 10:24 PM
Thread Starter
  #21
Jeeper
 
seanpsills's Avatar
 
Join Date: Jun 2011
Location: Hawkinsville, GA
Posts: 39
I checked my mileage and it is 14.5 mpg city driving. I love my jeep but with my 2.5L I can barely pull anything up hills and I don't mean mountains lol. Either I need to sell it or regear I guess. Would re-gearing be a viable option for pulling. I only pull a four wheeler on small trailer or jon boat. As of now, I can barely pull the four wheeler. Please advise.
seanpsills is offline   Quote
Old 08-27-2011, 10:29 PM   #22
Rock-Rubber

WF Supporting Member
 
GoldenSahara00's Avatar
 
Join Date: Aug 2010
Location: Central PA
Posts: 16,970
You need to get the smaller tires as I mentioned before.

I went from 20+ mph to around 15 average changing tires. so You could probably pull 18-19 with smaller tires. regearing is only going to get your power but your mpgs will still be bad if not worse with the 2.5. It wasn't meant to get good mpgs with big tires.

The increased weight of the tire, in addition to the increased size of the tires itself both play into mpgs. More weight at the wheels means decreased power. Because you have bigger tires, your going to be running at lower RPMS than you normally would at certain speeds. So you will get worse gas mileage. It also takes more gas to spin those same rpms. If you want to reduce weight, take of your spare and remove your rear seat. Clean your air filter, change your spark plugs, and make sure your exhaust is functioning properly. Thats about all you can do.

If you have the money to regear, your better off selling your jeep then buying a 4.0
__________________
Ryan - A good eye, a light foot, and a smart rig.
Bolt-ons are boring
AMERICAN JEEPER
My Build - https://www.wranglerforum.com/f118/pr...a00-74622.html
Rausch Creek Trip: 2014 Trip Coming Soon
GoldenSahara00 is offline   Quote
Old 08-27-2011, 10:36 PM
Thread Starter
  #23
Jeeper
 
seanpsills's Avatar
 
Join Date: Jun 2011
Location: Hawkinsville, GA
Posts: 39
golden i really appreciate the advice. What would you think would be the best tire size and can I get an aggressive all terrain in the size? Largest tire I can put on and be back to right.

seanpsills is offline   Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not 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


Similar Threads
Thread Thread Starter Forum Replies Last Post
WTB Stock TJ Air box, body mount bolts, and control arms subtlez28 Classifieds Archive 12 06-10-2011 01:05 AM
31" or 32" For Mileage saltlife TJ General Discussion Forum 5 01-17-2011 05:41 PM
Stock JK cross country questions Topless-in-the-Buff JK General Discussion Forum 8 11-08-2010 12:33 AM
Low mileage 99' TJ (lockers, 36's, LA's) Pinckney, MI GrnTJ Classifieds Archive 8 01-06-2010 07:10 PM





All times are GMT -5. The time now is 06:01 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.1
User Alert System provided by Advanced User Tagging v3.1.0 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.

Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, Gladiator, Mopar and Grand Cherokee are copyrighted and trademarked to FCA US LLC.
Wranglerforum.com is not in any way associated with FCA US LLC.