looking thru the search forum I still dont understand backspacing/offset but was wondering if this rim would fit into my 07 4runner, moto metal MO957 seem like it would fit with the right backspace of 4.53" but from the offset it seem to be at a high negitive 12mm.

It will fit, but it is going to stick out about an inch.

Great pictorial but does a negative offset mean the center of the wheel is left of the center line?

Yes.

You dont really need to know backspace AND offset. They are both are different ways of measuring the same thing - where the wheel mounting pad sits in the wheel.

Basically pick one method and use it. Pretty much all aftermarket wheels will have offset and baskspace info available.

Can you guys try to help me out here? I've tried to understand this stuff, but it's hard for some reason. I have my stock wheels and 1.25" spidertrax. What offset do I have to get for aftermarket wheels to get the same effect?

Thanks

Jack

Anyone care to note stock offset and/or back spacing for stock 4th Gen wheels and stock FJ wheels? Seems like this thread won't be complete without it.

It's my understanding their are 4 stock 4runner options, correct?

1. 16" SR5 -5 spokes
2. 17" Sport -6 spokes
3. 18" Limited -5 spokes (look like the SR5s just bigger)
4. 18" Urban Runner -6 spokes (look like Sports just bigger

All are 9" width? Or are they 7.5"

FJ stock options (a common swap) are hard to track down but according to this They are all 17x7.5"

FJ Cruiser Specific 16"17" Wheel/Tire Fitment Guide - Toyota FJ Cruiser Forum

Ad it seems like increasing offset/backspacing with wheels and/or spidertrax doesn't necessarily resolve rubbing issues, it might just change where the rub occurs?

1. 16" SR5 -5 spokes
2. 17" Sport -6 spokes
3. 18" Limited -5 spokes (look like the SR5s just bigger)
4. 18" Urban Runner -6 spokes (look like Sports just bigger



^ Wrong. SR5 are 17" rims. Urban Runners are also 17" I believe. There is a 16" Rim that came on early 4th gen 4runners though.

I believe those SR5 5 spokes are 17" as well. The urban runners I have seen have the same 18" wheels as the limited, with 6 spokes. I think they are all 7.5" wide.

In response to your other question, the 18" limited wheels with 1.25" spidertrax should have an effective offset of -6.75mm.

17" Sport wheels have a +30mm offset
18" limited wheels have a +25mm offset
17" FJ cruiser wheels have a +15mm offset

I think a separate thread with a pic of the wheel and a measurement of backspace only would be a great sticky. I will pull my stocks out and also my TRD's and post a photo of each and the corresponding backspace. If we keep the thread limited to that it would be a great resource for anyone trying to work out the changes they can expect with different set-ups. If someone is getting a new set of wheels, take the time to accurately measure the back space and post it with a pic of the wheel and brief description of same. Will start the thread and post initial pics tomorrow along with a description of how and what is being measured so we can all compare apples to apples.

I've been looking all over for exactly that!

Or even a excel chart showing stock measurements vs aftermarket sizing with the amount that it moves out over stock!

Im with him... I have 17" stock rims with 1.25 spacers. Im running 285/70r17 BFG KOs. What offset will I need if I go aftermarket? Staying with a 17x8in wheel.

Check out Tire Rack for tire/ wheel info

Wheel offset and backspace measure the same thing but in a little different way. They tell you where in the wheel well a particular wheel will sit.

Offset is a measurement in millimeters from the backside of the mounting plate to the center line of the wheel. A positive number puts the mounting plate further away from the backside of the rim. A negative measurement moves it closer to the backside. Since offset is based on the center line, the width does factor in. That is to say an 8-inch wide +45mm offset and 7-inch wide +45mm offset results in a 1/2" difference in wheel positioning. The 8-inch wide will be further into the wheel well. To gain a better understanding of the offset of a wheel, read our tech article on this topic.

Backspace measures the distance from the mounting plate to the back edge of the wheel. The higher the backspace the further into the fender well it will sit.

Here's a simulator.

Custom rims, wheel tire packages for your ride - RIMSnTIRES.com