Cherokee Chat General non-tech Cherokee chat
XJ/MJ/ZJ/WJ

the awful truth about tire sizes "thread"

Thread Tools
 
Search this Thread
 
Old Feb 18, 2011 | 05:00 PM
  #1  
N20jeep's Avatar
Thread Starter
CF Veteran
 
Joined: Mar 2010
Posts: 6,685
Likes: 6
From: Jacksonville, FL
Year: 92
Model: Cherokee
Engine: 4.0
Default

So, I end up having to do a lot of tires at the shop. And I notice most listed sizes don't reflect actual size. So I figured id make a list to show actual measurements of new tires and what wheels they're mounted on.

This info could also be used in deciding what gear ratio to use for which tire, since it reflects actual size.

So now every set I mount I will take measurements and add to the list. So stay tuned for updates

First up
31x10.50x15 bfg km2, mounted on a 15x8 wheel
-actual size...30x9

Last edited by N20jeep; Feb 18, 2011 at 05:06 PM.
Reply
Old Feb 18, 2011 | 06:56 PM
  #2  
Bustedback's Avatar
CF Veteran
 
Joined: Feb 2010
Posts: 12,367
Likes: 23
From: Oroville, CA
Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
Default

There is no regulation to the sizing, so a tire company can sell a 235-75-15 and it will be smaller than another company's 225-75-15. Goodyear has some models that run way smaller than some of their other models, even though they are listed as the same size on the sidewall.

Last edited by Bustedback; Feb 18, 2011 at 07:05 PM.
Reply
Old Feb 18, 2011 | 08:26 PM
  #3  
N20jeep's Avatar
Thread Starter
CF Veteran
 
Joined: Mar 2010
Posts: 6,685
Likes: 6
From: Jacksonville, FL
Year: 92
Model: Cherokee
Engine: 4.0
Default

Originally Posted by Bustedback
There is no regulation to the sizing, so a tire company can sell a 235-75-15 and it will be smaller than another company's 225-75-15. Goodyear has some models that run way smaller than some of their other models, even though they are listed as the same size on the sidewall.
O I realize that. But this is more of an informative thread on different actual sizes
Reply
Old Feb 18, 2011 | 08:40 PM
  #4  
xjmarc's Avatar
CF Veteran
 
Joined: Feb 2010
Posts: 5,420
Likes: 0
From: Soddy Daisy TN
Year: 97
Model: Cherokee
Engine: 4.0L
Default

I'll play, Mickey Thompson MTZs 35x12.50x15 on 8" rim measure 35.25. BFG KM2s same size on same size rim is a smidge over 34 1/2". Super Swamper tells you the exact size on their website, ie 37 is actually 36.75.
Reply
Old Feb 19, 2011 | 03:22 AM
  #5  
ivantheigor's Avatar
CF Veteran
 
Joined: Jan 2011
Posts: 1,375
Likes: 3
From: Maine
Year: 2000
Model: Cherokee
Engine: 4.0L I6
Default

Originally Posted by Bustedback
There is no regulation to the sizing, so a tire company can sell a 235-75-15 and it will be smaller than another company's 225-75-15. Goodyear has some models that run way smaller than some of their other models, even though they are listed as the same size on the sidewall.
You think that **** would be standardized by now....
Just makes for some upsetting moments.
Reply
Old Feb 19, 2011 | 03:58 AM
  #6  
Tural's Avatar
CF Veteran
 
Joined: Jan 2010
Posts: 3,379
Likes: 0
From: Forest, VA
Year: 1999
Model: Cherokee
Engine: 4.0 I6
Default

lol dude that works with me is in his third transfer case because of that... he's got a v8 zj, and had no idea that he needs to replace all 4 tires at the same time. he just thought that zj transfer cases don't last.
Reply
Old Feb 19, 2011 | 08:56 PM
  #7  
djlarroc's Avatar
CF Veteran
 
Joined: Jun 2009
Posts: 3,071
Likes: 0
From: Denver, CO
Year: 1997
Model: Cherokee
Engine: 4.0
Default

Also the Super Swamper Irok 36x13.50x15 is almost a 37 and actually taller than the 37.
Reply
Old Feb 19, 2011 | 09:05 PM
  #8  
HCCAFan's Avatar
CF Veteran
 
Joined: Nov 2010
Posts: 1,275
Likes: 2
From: North Carolina
Year: 1999
Model: Cherokee
Engine: Gas
Default

Most tire manufacturers have this info on their site.

I bought the "same size" tires as my friend. His are nice and wide. Mine look like pizza cutters.
Reply
Old Feb 19, 2011 | 09:27 PM
  #9  
Bustedback's Avatar
CF Veteran
 
Joined: Feb 2010
Posts: 12,367
Likes: 23
From: Oroville, CA
Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
Default

Originally Posted by HCCAFan
Most tire manufacturers have this info on their site.

I bought the "same size" tires as my friend. His are nice and wide. Mine look like pizza cutters.
Thats enough to **** off the Pope, right there.
Reply
Old Feb 21, 2011 | 09:30 PM
  #10  
xjmarc's Avatar
CF Veteran
 
Joined: Feb 2010
Posts: 5,420
Likes: 0
From: Soddy Daisy TN
Year: 97
Model: Cherokee
Engine: 4.0L
Default

Here you go. Mine are 35 MTZs on 8" rims and my buddy's are 35 KM2s on 8" rims. Both 12.50x15s. Mine are an inch taller and a bit wider as well. We both run 6 psi.
Attached Thumbnails the awful truth about tire sizes "thread"-cimg2341.jpg  
Reply
Old Feb 23, 2011 | 02:17 PM
  #11  
HCCAFan's Avatar
CF Veteran
 
Joined: Nov 2010
Posts: 1,275
Likes: 2
From: North Carolina
Year: 1999
Model: Cherokee
Engine: Gas
Default

6 PSI? Holy *****! I always thought 15 was low!
Reply
Old Feb 23, 2011 | 02:19 PM
  #12  
j-rod's Avatar
Senior Member
 
Joined: Sep 2010
Posts: 603
Likes: 0
From: Farmington WV
Year: 1996
Model: Cherokee
Engine: 4.0
Default

my MT Baja Claws in 33" measured 32.4"
and my SS LTB's in 34" measure 33.6"
Reply
Old Feb 23, 2011 | 02:21 PM
  #13  
rweaver138's Avatar
CF Veteran
 
Joined: Oct 2009
Posts: 1,640
Likes: 0
From: Northeast CT
Year: 99
Model: Cherokee
Engine: 4.0
Default

Originally Posted by HCCAFan
6 PSI? Holy *****! I always thought 15 was low!
beadlocks my friend
Reply
Old Feb 23, 2011 | 02:42 PM
  #14  
alloutperform's Avatar
CF Veteran
 
Joined: Nov 2010
Posts: 1,140
Likes: 1
From: cape cod ma.
Year: 1998
Model: Cherokee
Engine: 4.0 i6
Default

my old swamper trxus mts were 3/4" taller and wider then the bfg a/t i had on my spare at the time both 31x10.50...i tell all my customers that mickeys, swampers,and the more competition minded tires are closer to the correct tire size
Reply
Old Feb 23, 2011 | 08:41 PM
  #15  
xjmarc's Avatar
CF Veteran
 
Joined: Feb 2010
Posts: 5,420
Likes: 0
From: Soddy Daisy TN
Year: 97
Model: Cherokee
Engine: 4.0L
Default

Originally Posted by rweaver138
beadlocks my friend
Wish I had beadlocks. I run anywhere from 5-8 depending on terrain and I've broken a bead once, but I carry a CO2 bottle with 5000 psi so it ain't no big thing. And I run 15 on the road on those times I remember to air up.
Reply



All times are GMT -5. The time now is 05:19 AM.