Wheel offset and backspacing headache!

[goneboating06]

I have spent the past 4 hours trying to find some wheels i like for my Jeep. I want to run 33x12.5's and because of Utah's strict regulations the tire tread can't exceed the edge of my bushwacker flat style fender flares. So.. here comes the difficult part. I have found the rims i really like and they are the 15x8 ion alloy 174's. However they run at a 3.5 inch backspacing and i have come to the conclusion after many hours of research that they will stick past the bushwackers. So i dug deeper and found that same rim but a:

16"x8" 5X4.5 -5mm 4.25" 83.8mm.​

Now, can someone help me translate this haha. I understand that its a 16x8 rim, and that it has a 5x4.5 bolt pattern (which is what our cherokees have right?) The rest of it i have no idea what it means? Will this rim provide the proper backspace to keep the 33x12.5's within the fender flare coverage? What is the difference between backspace and offset? Sorry for all the questions

Here is the link for the wheels:http://www.jcwhitney.com/style-174-black-wheels/p2024164.jcwx?TID=LC00010&lc=1
Thanks!

 

[dart70LA]

-5MM is the offset. Measured from the center the offset is 5 mm less than than center.

(25.4(mm per inch) * 4inch(center) - 5mm)/25.4 = 3.8 inch offset.

 

[goneboating06]

Sorry for my incompetence, but just to make sure i understand correctly... the 16x8 is wheel size, 5x4.5 is the lug pattern, the -5 is the offset, and the 4.25 is the backspacing right? so would the 3.8 inches be the total backspacing? correct? what does the 83.8mm number mean?

 

[aintright]

just from what you posted the 4.25" is the back spacing. did you do the math to figure out your total track width for the new wheels. also did you measure to see what your total track width is right now.

measure from edge of flare, across the hood to the other edge of the flare.
that is what you need to match or stay under.

you could either measure your track width as it sits now. note tire size and wheel width, also wheel back spacing.

i thought about this awhile when i was going full widths, i think i have a way to figure it out.

 

[aintright]

with the 16x8 wheels with 4.25 back spacing your track width should be 76.5

axle width(60") + ((width of tire 12.5" - width of wheel 8")x2) + ((width of wheel 8" - back spacing 4.25")x2)

that should help. but do that then measure your track width and see. also have to think about the actual width of the tire. just because it says it's a 12.5 doesn't mean it's actually that it could be 12.3 or 12.6, check the manufacturers website for the actual measurements

 

[JSwamper]

I feel your pain. I just went through this so ill try and help you out.

I have the other style bushwackers. in the first pic and tires are really tucked in the fenders. Wheel spec: 33x12.5 15x8 4.25 backspacing

http://s1140.photobucket.com/albums/n580/mofohunter/?action=view&current=98xj-Front.jpg

I really hated the look of the tires being tucked in so I knew I would have to go wider withouth using wheel spacers.

after doing alot of reasearch I ended up getting 35X 12.5 15x10
3 5/16" backspacing. They probably stick out 1.5-2"

http://s1140.photobucket.com/albums...ofohunter/?action=view&current=98-newlook.jpg


the bushwackers are 6" wide

 

[goneboating06]

I feel your pain. I just went through this so ill try and help you out.

I have the other style bushwackers. in the first pic and tires are really tucked in the fenders. Wheel spec: 33x12.5 15x8 4.25 backspacing

http://s1140.photobucket.com/albums/n580/mofohunter/?action=view&current=98xj-Front.jpg

I really hated the look of the tires being tucked in so I knew I would have to go wider withouth using wheel spacers.

after doing alot of reasearch I ended up getting 35X 12.5 15x10
3 5/16" backspacing. They probably stick out 1.5-2"

http://s1140.photobucket.com/albums...ofohunter/?action=view&current=98-newlook.jpg


the bushwackers are 6" wide

Thank you for your post and the pictures!!!! This finally settled my frustration! Il lol.