31" tires, 235/75 15 spare ok? - JeepForum.com

Reply
 
LinkBack Thread Tools
post #1 of 27 Old 06-01-2013, 05:06 PM Thread Starter
ErikTheRad
Registered User
1993 ZJ 
 
Join Date: May 2010
Location: Marysville
Posts: 420
31" tires, 235/75 15 spare ok?

I'm buying a set of 31" A/T's for the Jeep, would like to keep one of the current 235/75 r15's for a rooftop spare instead of having to buy a 5th tire. I know ideally we should run the same size tires all around but would it be ok to use it as a limp-home emergency spare tire? Or will this screw up a front or rear differential? In some cases we're more than 150 miles from home, and at least 75 miles to the nearest tire shop.

ErikTheRad is offline  
Sponsored Links
Advertisement
 
post #2 of 27 Old 06-01-2013, 05:10 PM Thread Starter
ErikTheRad
Registered User
1993 ZJ 
 
Join Date: May 2010
Location: Marysville
Posts: 420
As usual, I find conflicting information. As far as I can tell, with my 249 transfer case kept in full-time, I should be ok for a short while but get it changed asap. Should be ok to get it home. Does this sound accurate?
ErikTheRad is offline  
post #3 of 27 Old 06-01-2013, 05:21 PM
cgcarpenter
Registered User
1997 ZJ 
 
Join Date: Jul 2012
Location: west covina
Posts: 758
I do not know much about the 249 bit as I've heard hundreds of times here. Jut get the same size tire or AS CLOSE as possible or you will be in trouble.
I'm sure someone with a 249 will chime in and say the same
cgcarpenter is offline  
post #4 of 27 Old 06-01-2013, 05:21 PM
jm8881
Registered User
1996 ZJ 
 
Join Date: Oct 2005
Location: Palm Desert
Posts: 849
It is not a good idea to drive on a mismatched tire for any amount of time, especially with an awd vehicle. Even on a fwd or rwd car you should make sure the drive wheels are the same size by swapping the flat tire with a good tire from the other end of the vehicle and putting the doughnut on the non drive wheels.
jm8881 is offline  
post #5 of 27 Old 06-01-2013, 05:24 PM
BLarkin
Registered User
1997 ZJ 
 
Join Date: Oct 2012
Location: Hickory
Posts: 170
Ive got the 242, but from I've read here about the 249, you do NOT want to mix tire sizes, or even tire brands. Those TCs are extremely picky about tire height, and you will burn them up running different size tires. At the very least, scour your local CL for a good used 31, probably find one for $50 or less.
BLarkin is offline  
post #6 of 27 Old 06-01-2013, 06:01 PM
PolkaPower
Registered User
1998 ZJ 
 
Join Date: Aug 2011
Location: The Abyss
Posts: 19,372
No effing way. You will kill that 249 fast with an odd sized spare. Especially with the early 249's. All tires need to be the same and do not remove the front shaft and drive it. That will kill the VC too.
PolkaPower is online now  
post #7 of 27 Old 06-01-2013, 06:05 PM
dnuccio
Registered User
1995 ZJ 
 
Join Date: Jul 2012
Location: Phoenix
Posts: 3,483
buy the 5th 31" tire. if you run the smaller tire for even a short time it will destroy the viscous coupler in the transfer case.

Reliability is relative
R.I.P. Ratmonkey
dnuccio is offline  
post #8 of 27 Old 06-01-2013, 06:30 PM
JasonStebbins
Registered User
1997 ZJ 
 
Join Date: Jan 2009
Posts: 3,138
No. Unless you want to buy a new transfer case and front end.

Poop
JasonStebbins is offline  
post #9 of 27 Old 06-01-2013, 06:38 PM
4x4andmetal
Registered User
1996 ZJ 
 
Join Date: Mar 2013
Location: Savannah
Posts: 92
I have a 249. One time I put a different sized tire on because I had a flat. I ended having to replace both differentials. I also only drove about 5 miles.

1996 4.0 Laredo. Weekend warrior
1999 Pontiac Grand prix GTP. Daily driver
1995 318 laredo. Gone
4x4andmetal is offline  
post #10 of 27 Old 06-01-2013, 10:40 PM
Myusername1674
Registered User
1995 ZJ 
 
Join Date: Dec 2011
Location: Chattanooga
Posts: 2,310
From what I've heard thats a bad idea, I spent the extra money and got a 5th spare from what I've heard its pretty necessary.

95 FiveTwo ZJ, DD, Lifted, Locked on 35s, Build (in progress)

My 5.9 swap (in progress)

Want your zj to be doorless in 60 seconds?
Myusername1674 is offline  
post #11 of 27 Old 06-02-2013, 12:43 AM
eagsc7
Registered User
1994 ZJ 
 
Join Date: Apr 2013
Location: Sweetwater Cyt
Posts: 433
So I shouldn't use the donut on my 33" tires either?

Only thing I've seen is that there was a Drivetrain issue with the 96 ZJs not working AT ALL with the doughnut spare. Course, There was a RECALL that's strangely ONLY for that year...
eagsc7 is offline  
post #12 of 27 Old 06-02-2013, 03:54 AM
PolkaPower
Registered User
1998 ZJ 
 
Join Date: Aug 2011
Location: The Abyss
Posts: 19,372
With the 249 all tires must be the same size. That is the bottom line.

96-98 it's ok to remove the front shaft and it won't hurt the VC or roll. 93-95 it's not ok. The power split for 93-95 is 50/50 all the time. For 96-98 it's like 10/90 front to rear until the rear tires slip.
PolkaPower is online now  
post #13 of 27 Old 06-02-2013, 04:19 AM
Texas ZJ1
Jeep Jedi Master
 
Texas ZJ1's Avatar
1994 ZJ 
 
Join Date: Mar 2003
Location: Omaha
Posts: 20,302
Polka is correct. Using a smaller or mismatched spare is very, very bad. You will destroy a 249 and if you have a traction aid like a locker or limited slip with any other transfer case, you'll destroy it as well. Do not do that. Buy the matching spare.

Hunter

04 4.7 HO, limited

08 Z71 Suburban, front leveling kit with rear spacers. 285/65 18s Nitto TerraGrappler G2s

94 5.9 Laredo 6.5 RE lift with 35 Maxxis Bighorns
and 33 Bridgestone Duelers
Detroit and true trac
Red Jeep Club Member
REDNECK JCM
Texas Jeep Owner #6
USN Jeep Club #4
http://www.kevinsoffroad.com/
602.841.3355

For your performance needs:

kolak@kolakperformance.com
480.998.366
Texas ZJ1 is offline  
post #14 of 27 Old 06-02-2013, 04:35 AM Thread Starter
ErikTheRad
Registered User
1993 ZJ 
 
Join Date: May 2010
Location: Marysville
Posts: 420
Well I guess that answers that. No can do. And if the 249 is THAT picky, then I probably shouldn't even mismatch with a 31 of a different brand or one that's been worn down. Rats, more money.
ErikTheRad is offline  
post #15 of 27 Old 06-02-2013, 05:12 AM
PolkaPower
Registered User
1998 ZJ 
 
Join Date: Aug 2011
Location: The Abyss
Posts: 19,372
Quote:
Originally Posted by ErikTheRad View Post
Well I guess that answers that. No can do. And if the 249 is THAT picky, then I probably shouldn't even mismatch with a 31 of a different brand or one that's been worn down. Rats, more money.
That is correct
PolkaPower is online now  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com 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 e-mail address for yourself.



Email Address:
OR

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.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



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 On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome