Found my rubbing, check my tire/ wheel math? (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

re_guderian

SILVER Star
Joined
Jun 17, 2005
Threads
165
Messages
5,045
Location
Arizona
Bought truck a week ago with Ironman Nitro lift (has Icon springs in the back, fwiw) and 285/65/18 Toyo AT2's on stock 18" wheels.

Found the source of my rubbing...

Screenshot_20210323-231452_Gallery.jpg


I'm planning on 255/75/17's on 4Runner TRD off-roads, at +15mm offset v stock +25?

SmartSelect_20210323-155052_OfferUp.jpg


They're 7.5" wide v stock 8"?

So I should gain 10mm clearance between the sidewall and UCA from the reduced offset, moving the wheel further outboard, another 6mm from the narrower wheel (12mm/2), and an additional 15mm from a narrower tire ( (285-255)/2), for a total of 31mm (1.25") additional clearance? I give up .5" in diameter, or .25" of ground clearance, and gain a touch of sidewall, and get rid of my UCA rub.

Sound right?

Will be going to either Ironman or SPC UCA's soon, and I think both of them might stick out further than OEM?

I'm considering the BFG MT KM3's. Had a set on my 100, and they were surprisingly quiet (or I'm getting old and deaf, good either way...)

I wish there was more than one option in 33x10.50x17, which is just a touch bigger than a 265/75/17, which nobody makes :(. The Kenda Klever R/T looks to be the ticket to gain back some ground clearance, but I know jack about the brand. It's also E rated, which I don't need, nor want the stiffer sidewall. It's 50 bucks cheaper per tire than the BFG, though.

Amazon product ASIN B07RRS3YYS

I seem to have scads of clearance fore and aft, with no visible signs of rubbing on the plastic, nor anywhere close to the body mount. Since most of my gains in clearance should be on the inner side of the tire relative to the current setup, and they are slightly smaller in diameter, I can't see this setup rubbing fenders or requiring BMC, though I haven't crossed it up yet.
 
Last edited:
  • Like
Reactions: r2m
The standard 6 spoke 2011 GX wheels (not sure if that's what you have) are 18"x7.5" wide with a +25mm offset, while TRD OR are 17"x7.5" with a +15mm offset, so the wheel alone will bring the tire 10mm closer to the UCA/Suspension.

There's several folks here who run TRD Pro/OR wheels, though not sure if they're genuine or aftermarket with a higher offset. Hopefully they'll chime in.
 
The standard 6 spoke 2011 GX wheels (not sure if that's what you have) are 18"x7.5" wide with a +25mm offset, while TRD OR are 17"x7.5" with a +15mm offset, so the wheel alone will bring the tire 10mm closer to the UCA/Suspension.

There's several folks here who run TRD Pro/OR wheels, though not sure if they're genuine or aftermarket with a higher offset. Hopefully they'll chime in.
Hey jmanscotch,

I believe the lesser the offset number the more it sticks out. So a +15mm wheel will be 10mm further from the UCA than +25. It measures the distance from the mounting faceplate to the center of the rim. So the lesser the the distance, the closer the mounting face plate is to the center of the rim, which would push the wheel further out
 
The standard 6 spoke 2011 GX wheels (not sure if that's what you have) are 18"x7.5" wide with a +25mm offset, while TRD OR are 17"x7.5" with a +15mm offset, so the wheel alone will bring the tire 10mm closer to the UCA/Suspension.

There's several folks here who run TRD Pro/OR wheels, though not sure if they're genuine or aftermarket with a higher offset. Hopefully they'll chime in.
Yes, should have clarified that I am running the standard six spoke wheel. Thanks for clarifying that they are 7.5" wide, so I'd lose 6mm from calculation. A smaller positive offset should move both edges of the wheel outboard, no? :lol: This is why I'm double checking before I drop a grand on tires :lol:
SmartSelect_20210324-063404_Gallery.jpg
 
You guys are right about the offset, I was visualizing it wrong! I always get it mixed up when it’s not fresh in my mind lol.
Amen, brother, that's why I'm appealing to the collective wisdom! The wheel wells on these just seem unnecessarily tight. 100 series anything under a 305/75/16 would fit no problem.
 
Kenda makes great tires for two wheel toys but I have no experience with the automotive line. I have seen some run those on 4Runners but I can't speak to their opinions on them.
 
New wheels and rubber on! Falken Wildpeak AT3W in 275/70/17 on TRD off roads painted black with Lexus emblems on the center caps and black lug nuts. No rubbing on the UCA, still need to stuff a wheel, but plenty of clearance on pavement.
20210330_154038.jpg
 
Last edited:
  • Like
Reactions: r2m
Took it out to the local playground to test out the new wheels and rubber. My first time off road in the GX, and it did not disappoint! Better than my 100 series!

20210402_131207.jpg


And this is why I went with the C rated Falkens instead of an E rated tire. 16 psi soaked up the rocks and allowed great traction up and down the washes...

20210402_123903.jpg


And a few more for fun...

20210402_123935.jpg

20210402_130703.jpg
 

Users who are viewing this thread

Back
Top Bottom