Wheel Backspacing and Offset Info

So the calcuations are the 5.25 BS minus the 1.25 spacers plus .5 inches for the larger rim is the 4.5 " BS. is this correct thinking?

Thanks again for your help

 

Additional width has no affect on backspacing. It's an independent measurement. Sonifnyounhave a 7" wide wheel with 4.5" bs, and an 8" wheel with 4.5" bs, all of the additional inch will be on the outside edge of the wheel.

 

Well finally my first post. I have a 2011 taco dcswb TRD off road. Looking at picking up some rims and wanted your expertise KPT. I have scanned through the posts and have not seen this size mentioned nor have I seen you stumped yet so here goes. I have the tsb springs and billies set a 1.75. Will these rims fit and what biggest tire you think it can handle with minimal or no trimming. The wheel specs are;
Bore-106.2mm
Offset-+0mm
Bolt pattern-6x139.7
Size-16x8.5
Your expertise is greatly appreciated!

 

Bump. I'm new to this.

 

Which wheel would fit better on a 2013 trd sport dblcab???? (Fuel Trophy 551) 17x8.5 -6 offset 4.5 backspacing or ( Method) 17x8.5 0 offset 4.75 backspacing. Toyo A/T II Open Country 265/70/17. I have stock height suspension. Thanks in advance

 

Ether one is fine

 

does the 17x9 , 4.5bs ,-12 ofset stick out of the truck with 265/70/17 and with the 285/70/17 thank alots

 

The wheels themselves will stick out 2.5" more than stock

 

I put 18x9s - 0 offset with 275/65/18s on a 2011 Tacoma DC Prerunner with a 2 1/2" lift.

No rubbing and kept the mudflaps

 

I'm sure this kind of question has been asked plenty of times on this thread, but I'm looking for decent, black, steel or aluminum wheels that give the right amount of offset/backspacing to make my 275/65/16's stick out about two or three inches from the fenders of my truck (if that's even possible). Any amount of help on this would be awesome! Thanks!

 

So I though offset and backspacing were the same? Expect offset was the metric measurement and backspacing was an imperial measurement.

For instance, my rims are 9" wide with a 0mm offset, so the backspacing should be 4.5" right?

 

No.

BACKSPACE measurement NEVER changes regardless of wheel width.

OFFSET measurement is relative to wheel width.

 

Sorry to bother everyone but I need to understand this.
I am trying to find out how much a wheel will stick out in comparison to stock. I know I should go with 4.5 inch backspacing.

First off, stock TRD OR alloy 16" wheels are 7 inch +32mm offset????

Mathematically, which I probably have wrong.

(1/2 rim width)-(offset)= distance from mounting surface to outside rim??
stock would be:

3.5-32mm(1.25 inches)= 2.25 inches

Going with 285/75/16 on 16X8 or 16X9 rims 4.5 Back spacing offset unknown

I also have a 1.25 in spacers so I would add to the figure above and get 3.5 inches

When I measure I am incorrect. I would like a rim that would stick out about 1 to 2 inches more than what I have and eliminate the spacers.

Help???? I am just not getting it.

going with 285/75/16 on 16X8 or 16X9 back spacing 4.5 offset unknown

 

16x8 with 4.5" backspace = 0 offset

16x9 with 4.5" backspace = -12 offset

It is pretty confusing.

 

So if my rim is 9" wide, and 0mm offset, that means the mounting surface is dead center of rim, why is backspacing not exactly 4.5"?

 

9" width wheel is measured inside rim to rim. Add 1/2" x 2 for the two rims.
If you lay a 9" wheel, flat on it's back and measure from the floor, up to the front, it's 10"
Backspace is measured from mounting surface to outside of rim
See picture in 1st post, this thread.
I made some simple drawings, here, to understand it myself
Should clear it up for ya.
picture's worth a thousand words, etc.
BTW, the term "rim" refers to the metal portion of the wheel, that the tire bead makes contact with.



CC

 

will I run into rubbing issues on the uca with 17x9 and 0 offset wheels on 285/70/17?

 

This is the part I didn't realize. Thank you.

 

I think I'm doing this correctly (probably not though). I have stock 17" TRD sport wheels on now. I am getting a set of 17x8 with 4"BS and -13mm offset. Does that mean the new setup will stick out 2.01" more than stock? I'm taking the 1.5" difference in BS and adding the -13 offset (.51") together.


How'd I do?

 

That's not actually the right way to do it, but you came out with the right answer.

the 1.5" less backspacing should be added to the 0.5" additional width to make 2.0".