So i could run spacers with a 285 on stock wheels and not have a rubbing problem.... can this b done without any lift at all??..or should i at least do a leveling kit.. i have a 2012 2x4...thx

 

at least a leveling kit and You would have to chop the body mount if you want spacers.

Chris

 

great info! thanks!

 

Aaaaahhhhhh! Wow, I need to read this one again! The square root of my UCAs divided by the backspace ....

Seriously though, thank you for taking the time to post all this info. I have actually been genuinely confused if when I upgrade my stock 16" wheels, do I go 16 or 17 and do I go 8" or 9" wide. Once I digest the info, this should help. Initially, I was thinking going up to 17". I'm now thinking 285/70/16 now with a 3" lift and new UCAs. I'll see if that will still be good. I hadn't thought too much about the brakes.

 

This is by far the most helpful thread I read on the forum (been a member for more than 2 years)

Thank you very much SN95cobra [OP], i certainly am enlighten

 

Great post. Very helpful. You only left out the 305/70 tire (or 33 x 12.5). Thank you for taking the time to explain.

 

No, he included them. Read again. Anyway, I have some 33x12.50 mud claws with a 2 1/2" leveling kit and they don't rub. I'm pretty happy with them. :grin

 

Wow I'm glad this thread was found and brought it back. This has answered a lot of questions I wanted to ask!

Sometimes old threads need love too...

 

Hi guys can I run my 3ich lifted Fj on 18s and 33 12.5 tire and am off roading
2 days a week what you guys think

 

Very awesome analysis of the subject!!! A lot of time, thought, and studying must' have gone into this!! Great job and thanks for taking the time to put this together!!

 

added a few more sizes and fixed some errors
added a section on load ranges
Thanks for reading
Chris

 

Thank you Chris. interesting thoughts on 295 and 305. much appreciated

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You have the 305/70/17 listed as a 33" tire, (there are only a few manufacturers of this size) but the spec size on a Goodyear Duratrac MT/R and BFG KM2 are both 34.1"

BTW Great thread!

 

sorry, good catch on the sizes
fixed

 

Great info in here, thank you.

I have finally found a wheel I like that is available in both 16" and 17" and both sizes are confirmed as being able to mate with my 2012 FJ. They are Method Race Wheels and the models I'm looking at are "The Standard" and "The Double Standard". Products – Street Wheels Method Race Wheels. The 16"x8" has 0mm offset with 4.5" backspace. The 17"x8.5" has 0mm offset with 4.75" backspace. If I go with 16" I'm planning on running 285/75/16, and if 17" it'll be 285/70/17. My question is which should I go with, 16" or 17"? What is pro/con to each aside from 16" being less expensive package?

 

16" wheel lets you air down better for offroad, and more tire options in 16" sizes than 17"

 

thanks... have been running original KM, now going to KM2 and was wondering if wheel spacers (1.25") would cause a problem with stock 17' wheels...
Glad the search popped up your thread!!

 

Well I am Going to add my 2 cents worth to this subject.....

2007 Fj 6speed base model w/3 inch OME lift.....Nitto Trail Grapplers 295x70rx17's on stock wheels do not seem to come close to the body mount but rub pretty hard on the UCA's....fortunately i had ordered a set of Light Racing UCA's and will put them on in the next week....I also have a set of 25mm (1inch) spacers I am going to try as I am going to do the body mount chop when I am installing the UCA's.

 

Ohhhhh and here is a pic.

 

Update
Installed the 1 inch wheel spacers today..... No rubs anywhere, but it gets within 1/2 to 3/4 of an inch of the body mount. I am guessing it might rub there under full compression so body mount chop on the way!

 

Will 285/70/17 mounted onto the stock 17" FJ alloy rub without a lift or BMC? Or is a lift absolutely necessary?

 

I have the same question. I want to run the BF Goodrich MT KM2 285/70 17" on fuel octane rims , not sure which width rim to choose. Thanks

 

 

kengray I looked up the fuel octane wheels and they only come in one 17" size - 17x8 with -5mm offset which means 285's will fit fine - if you're not going to lift then you'll for sure need to trim the body mount.

 

This may also be helpful to you.

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

 

Hey thats a cool toy, thanks for the link Woodsman.

 

I almost understand this now, thank you.

 

Wouldn't it be amazing if tire manufaturers just made the tires the size they should be. -Would definately help a lot of folks.

 

And wheels!

 

Stock FJ cruiser wheel sizes
16x7.5
17x7.5
6x5.5 (6x139.7 metric) bolt pattern
15mm offset or 4.84" backspace

I'm going to suggest a 3" lift for any of this information to be useful to you.
Get out there and at least buy a rough country/ome/procomp/revtek/icon/toytec 3" lift something anything it will be the biggest benefit offroading you can purchase.
Owners with 6" lift can use lots of this but have a bit more play on how wide they can go because of their higher front end

Right off i'd like to say that wheel sizes are measured from inside the wheel lip. so take a tape measure to a 16x8 wheel and you'll notice from outside to outside both ways it will actually measure around 17x9. inside lip to inside lip is 16x8.
The reason i'm pointing this out first is because of how the 2 methods of backspacing and offest are measured.

Backspacing can always be measured by putting a straight edge against the inside of the wheel and measuring from the inside of the hub.
How to measure backspace(Borrowed from TCao)

To measure Offset you need a metric tape measure. so run the straightedge along the inside of the wheel just like measuring backspace. then take that number and subtract half the wheel width. Your answer can be a negative number of course.

You can always figure out one if you have the other. For example:

16x8 wheel has 4" backspace. the wheel is actually 9 inches wide outside to outside so that means 4.5" would be center or 0mm offset. so you're 1/2" inside of wheel = -13mm offset

16x8 4"backspace -13mm offset
16x8 4.5"backspace 0mm offset
16x8 5"backspace +13mm offset

So the more negative the offset - the more the wheel will stick out of the wheel well.

Where can your tires rub on your FJ and is that a bad thing?
Yes it is bad to rub. If your tires are rubbing under normal driving situation then you can be sure that damage is a possibility on the trail. Thats why figureing out your wheel offset and true tire size are important.
Rubbing spots to watch for -
Body mount
Front wheel wells above body mounts
Upper control arms
Front Sway bar
Rear Wheel wells at the back and top


One quick note about load range letters on tires. I've seen C, D, and E tires on this forum. If you drive your truck at all you probably want a D. This letter is on every single tire on the sidewall and you can ask your retailer before you buy tires to confirm you are getting D load range tires. Some people might disagree on this point but C is too soft for the weight of the FJ. The tread will wear down rapidly plus rock rash and chunking offroading can be accelerated. Now a C load range winter tire would be a fine thing if you have a dedicated set of winter tires. The rubbers softness helps it from getting really hard in cold temperatures and maximaizes traction. E is a little different. Usually E rated tires are for full size 3/4 ton trucks and up. However some of the rigs on this forums are surpassing the weights of 1 ton trucks with all the armor and such on them. You're going to be hard pressed to wreck that hard rubber on rocky trails and you're going to get a lot of miles outta them because the tread is not going to wear fast. You'll also have trouble airing them down for the trails though.


So this thread pertains to wheel and tire fitment and i'll cover some info UCA and body mount chop but any other rubbing or fitment problems will not be covered (such as "my rear 35 inch tires rub the fender at full compression" problems)
If you're looking for a good Body mount chop thread here ya go..
http://www.fjcruiserforums.com/forums/4x4-off-road-tech/137777-different-kind-body-mount-chop.html


16" wheels

So we all know by now that 16 inch wheels are hit or miss with clearing the brakes on the FJ Cruiser. There are the 2 main threads on which 16 inch wheels are proven to fit and you can search through them if your heart is set on 16" wheels, which is a great choice btw. The reason why some fit and some don't usually has to do with the design of the wheel spokes and if they are curved enough or set out far enough to clear the caliper. This is not included in wheel manufacturers measurements so it is always an unknown factor.

Here's the 16" wheels that fit without spacer thread - super cool read...
http://www.fjcruiserforums.com/forums/wheels-tires/110002-post-all-16-rims-fit-without-spacers.html

Basically if you're looking for a 16" wheel, you need a

16x8,
6x5.5 bolt pattern,
and 4" - 4.5" backspace (-15mm to 0mm offset)
or 3.5" backspace ( -30mm offset) could be used for pizza cutters

the research on whether or not they clear the calipers is up to you.


17" wheels

So 17 inch wheels will definatly clear the brakes. Now 17inchers commonly come in different widths. 17x7.5(stock fj size) 17x8 and 17x9 are the most common FJ sizes.

17x8 you want around 4 - 4.5" backspacing ( -15mm to 0mm offset)

17x9 you want around 4.5 - 5" backspacing (-15mm to 0mm offset )notice a trend in the offset???
And i'm going to get into some odd size wheel backspaces and widths in this next section, so read on.


Fitting some Big Bad tires on your new wheels...
Don't worry, offroaders aren't the only ones struggling to fit tires into wheel wells...

So now that we've covered the basic sizes and backspacings. Lets look at fitting some tires to those wheels.


so stock fj cruiser come with 17x7.5 wheels with 265/70R17 Dunlops. (32x11)

so you actually have a wheel that is 8.5" width. And the dunlops measure 10.8" section width. 2.3" difference.

so your tires is bulging out 1.15" on each side of the wheel.


Pizza Cutters - 255/80R17 or 255/85R16 (33x10.5)

When you like pizza cutters then you want a wheels with less backspacing or else wheelspacers. So for a 16x8 or 17x8 wheel you want around 3.5" backspace. Or run wheelspacers with any stock FJ wheels. The good thing about this size is they are usually a 33.3" tire, nice and tall.



Now lets look at 285/70R17 or 285/75R16 (33x11.5)

stock wheel again 17x7.5
this particular 285 measures out to 33" x 11.6"secwidth

so your tire will stick out 11.6-8.5=3.1 divide in half

1.55" on each side.

not too outrageous at all. This a great wheel size for FJ's with a 3" lift and almost garunteed no rubbing while offroading.


Now i want to look at the 295/75R17 Nitto Trail Grappler which has become famous on this forum because of it's seemingly stock fitting ability.

It's a great tire that measures 33.54" diameter x11.97" section width.

so stock 17x7.5 wheel again
11.97-8.5=3.47 divide in half =
1.735" bulge on your wheel

and it's still short enough that it doesn't come into contact right where the arrow's pointed at with the UCA(thanks willaim99740)

305/65R17 or 305/70R16 (33x12.5)

These tire are a little wider than the 285's. Usually people have rubbing problems at the body mount more than anything and you find lots of people with this size tire use wheel spacers and can get away with it because the tire is still not too tall. Should have a wider wheel than stock FJ wheels because of the width and smaller sidewall than a 35.



285/75R17 (34x11.5)
Only nitto and toyo make this size (found bfg AT does too) I think and only in a E compound
It's a nice tall skinny size though and if you have a lot off weight added to your rig (bumpers, skids, roofracks, sliders) you could almost probably run a E range tire. Won't air down for the trails very well though because it's so stiff.


305/70R17 (34x12.5)
This is basically what it says for size, take a look at 35's below to see what you should do to make these fit as they are only really about 1/2 less dimeter.


315/70R17 or 315/75R16 (35x12.5)

Basic rule: if you want to fit big tires keep them as close to the UCA without rubbing as you can. fitting 35" tires on the fj is difficult for a few reasons. Body mount chop is 100% neccesary. aftermarket Upper Control Arms are not 100% neccesary but make life alot easier.


So first off i am running 315/70R17 mickey thompson MTZ's on stock wheels with no spacers and i rub my total chaos UCA's a little bit at full lock, which i have chosen to live with.

so these tire measure 34.6 x 11.9

about the same tire width and sidewall bulge as the trail grapplers with about 1" more overall diameter. And that 1" bigger diameter means the tire sits higher and rubs (at least mine do) on the area pointed out in the william99740 pic.

If i were to throw on a 17x8 wheel with 4.5" backspacing (basically a half inch wider wheel with the half inch sticking out and no more wheel sticking in) that would move my tire out 1/4" inch.

If I would throw on a 17x8 wheel with 4" backspace it would move my tire out 1/2"

All that math to move the tire 1/4"or 1/2" out. which i could because i know theres room at the body mount still because i chopped it aggressively and a 17x8 inch wheel would mean less tire bulge and less risk of popping a bead.


WheelSpacers

sure you can run wheelspacers but the most popular is 1.25" spidertrax here on blue forum. So lets say you got stock wheels again. Basically you're changing your backspace from 4.5" to 3.25"

So your going to have tons of clearance at the UCA.
Your going to have a wider stance and better Center of Gravity.
and if you're only want to run 33" then those are great benifits.

But you're moving the rubbing problem extremly to the body mount. so this will limit how big of a tire you can run. There's no way i can run spidertrax with the 315 mtz's i have about 1/2" at the body mount right now so that means about 3/4" of the tire would be stuffed into that body mount when turning.





In saying all that...

If you read this all i hope you came away learning something. And there will still be questions on fitting tires regardless of how good a fitment guide someone writes or a forum puts together. Anything you don't agree with or want me to change or something you think of let me know.

:cheers:
Chris

Thank you for sharing such quality information. Please excuse me for still asking further questions as I'm new to upgrading and want to make sure I take the right decision as I love my car and so does my little kid.

I want to lift my car and put bigger tires without having to do a BMC job. Can you please tell me what is the max size tires I can use with 16" stock wheels? I was thinking of the BFGs 285/75/16 with an icon or fox 3"lift. Is that a wise choice?




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