I have a set of Firestone Transforce AT I pulled from my truck and was wondering what I would need to install this on my 2006 SE. It's time my 4R to get new tires so I figure I might as well use these.

I looked at the Suspension Options/FAQ sticky but there were no mentions of 275/70-18. From that post, it looks like the Cornfed and Toytec spacer lifts both net 3/2 lift and I was thinking of going with either of those. I also found that I would also need 1.25" wheel spacers. With this setup, will I need to do any trimming? (Trying to avoid any trimming). The Transforce tires is not an overly aggressive tire so hopefully it lessens the chances of rubbing.

You "might" need to do minimal trimming...at least push in your front fender liner and/or throw a screw into your OE mudflaps to adjoin to the OE running boards...The lift will get you the height and the spacers will help push the tires out to help eliminate any rubbing on CAs, etc...

Wait, are you talking about a 4th Gen or 3rd Gen?

4th gen - 2006 SE. The 3rd gen in my sig was my previous 4R...

On the 2006 4runner I'm running BFG KO2 275/70/17 on the SEMA TRD Pro rims with a 2.5" OME lift only other mod was removal of the front mud flaps.

SEMA PRO 17" x 7 RIM Specifications;
Offset - 4mm
Backspacing - 4.25"
Bolt Circle - 6 On 139.7 mm
Dia - 17"
Wheel Width - 7"

Not sure what 18" rims would have a similar offset and backspacing to get the same non-rubbing fitment. You might try My Bolt Pattern | A Bolt Pattern Chart for Selecting Custom Rims to Fit Your Car or Truck to see what you can find. Make sure what ever rims you find have the same wheel width as your tires and center centric mounting.

Boort

Hmm...didn't think about having a smaller offset to omit the use of wheel spacers.

Currently I have the stock wheel which I believe is 7.5" wide with an offset of +30mm. Is this correct for calculating the backspace width from the rim centerline:
7.5/2 = 3.75"
+30mm is roughly 1.18"
The backspacing is 3.75 + 1.18 = 4.93"

If this is correct, would it be safe to assume anything less than 4.93" clears the UCA?

Yours has a 3.66" backspacing - which is why it clears the UCA. Do I have that right?

I'm thinking of getting these that are 9" with 0 offset:
Vision Nemesis Wheels | Mesh Truck Painted Wheels | America's Tire

Since it's backspacing is less than 4.93" (backspacing is 4.5"), would these work?

@benjamin247

My reason for switching to the TRD SEMA rims was to both lower the weight and get the lower offset. IIRC staying with the stock wheels was +~5lbs and adding spacers was another +3.5-4lbs at each corner. Since I was already adding weight with the bigger tires I wanted to avoid any unneeded weight and rolling resistance.

The backspacing calculation I have in my notes is:
A wheel’s backspace is equal to ½ the wheel’s width + offset (in inches) + ½”
So that would be:
7.5/2+1.18+0.5=4.16

As for clearing the UCA you are talking about going to 18" rims which since the UCA and shock/springs are at an angle relative to the rim's mounting surface gives you a bit more room than the 17" rim would. but may position the tire sidewall, esp. when aired down for offroad, closer to rubbing on the shock/spring assembly.

9" wide rims are a tough fit on 4runners based on my conversations with the team at Slee Offroad (They did my lift and tire fitment last year.) @1engineer 's post in the 5th gen forum goes into this in far more details much of which applies to the 4th gen. Changing Tire Size or Wheels? Read this first! - Toyota 4Runner Forum - Largest 4Runner Forum

Boort

Good to know. Thanks Boort! Now excluding 9" wide rims from my search...

275/70/r18 is a 33”+ tire I am pretty sure you may need a body mount chop. I have 33” tires on my 20” wheels and I had to do body mount chop and also remove mud flap, carve off some of fender, and push liner forward. Also added a considerable amount of lift 3.5” or so in the front. 4th gen has the smallest space for large wheels of all generations it seems..
I may have carved a little extra to be on the safe side, because immediately after installing the 33” tire even with the lift it rubbed terribly with the 33” tires not even driveable to even be reasonable to do any medium to sharp turning without rubbing terribly and making a horrible sound. (Before body mount chop)

The rear won’t need much work at all, mine rarely rubs if I turn into a driveway and drive the rear tire over a curb while turning fast it’ll heit the rear mudflap very briefly but not under normal street conditions, I do plan on leaving the mud flap in but putting in a flat screw cus I don’t mind the rubbing on the plastic but I’m worried the bolt style screw that screws the mudflap in will start chunking off pieces my tire of it does rub often enough.

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