Notices
Modified JK Tech Tech related bulletin board forum regarding subjects such as suspension, tires & wheels, steering, bumpers, skid plates, drive train, cages, on-board air and other useful modifications that will help improve the performance and protection of your Jeep JK Wrangler (Rubicon, Sahara, Unlimited and X) on the trail.

PLEASE DO NOT START SHOW & TELL TYPE THREADS IN THIS FORUM
Sponsored by:
Sponsored by:

back space

Thread Tools
 
Old 02-13-2018, 05:41 PM
  #1  
JK Newbie

Thread Starter
 
acanthus's Avatar
 
Join Date: Nov 2016
Location: Custer, SD
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default back space

What is the required backspace for 35 inch tires on a JK?
Old 02-13-2018, 06:38 PM
  #2  
JK Jedi Master
FJOTM Winner
 
nthinuf's Avatar
 
Join Date: Jan 2008
Location: Austin <--> Colorado Springs
Posts: 11,465
Likes: 0
Received 162 Likes on 154 Posts
Default

Required?

The general recommendation for a 35x12.50 is a 4.5" backspace. Recommendation. There are variances in tire height and width, in actual measured lift height, in the choice of fender flares and whether someone is ok with trimming or adding washers to steer stops, and the list goes on.
Old 02-13-2018, 06:55 PM
  #3  
JK Newbie

Thread Starter
 
acanthus's Avatar
 
Join Date: Nov 2016
Location: Custer, SD
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
Default

Is the backspace measured from the inside of the wheel or the outside of the rim? I am currently running stock 18inch wheels with 34 inch tires with 1 1/2 inch spacers. I would like to move to 17 inch wheels and 35's and get rid of the spacers. Hope this isn't a stupid question. Vehicle is a 2007 JKU Sahara with 2 1/2 Teraflex lift.
Old 02-13-2018, 07:30 PM
  #4  
JK Jedi Master
FJOTM Winner
 
nthinuf's Avatar
 
Join Date: Jan 2008
Location: Austin <--> Colorado Springs
Posts: 11,465
Likes: 0
Received 162 Likes on 154 Posts
Default

Stock rims should be 6.25" backspace. Minus the 1.50" spacer, gives you an effective backspace of 4.75" right now. So new rims with a 4.50 would put those same tires 1/4" further out (assuming the same width rim.) Then there are the variables of new rim width, actual measured height and width of the tire, etc.

There are plenty of diagrams online that will show backspace better than I can explain it, but it is measured from the back edge of the rim to the inner mounting surface.

Nope, not a stupid question. People ask about this and offset all the time. It's just that there is not a single 'correct' answer that will work for everyone, too many variables.

Last edited by nthinuf; 02-13-2018 at 07:40 PM.
Old 02-14-2018, 06:06 AM
  #5  
JK Freak
 
Wandell's Avatar
 
Join Date: May 2011
Location: Cairo, GA
Posts: 868
Received 8 Likes on 7 Posts
Default

The most common setup is a 9 inch wide wheel with 4.5 inches of backspacing.



Quick Reply: back space



All times are GMT -8. The time now is 03:01 PM.