Aftermarket wheel offset question

[lobodog1]

I am about to pull the trigger on a GX here in the near future and have been pre-planning what I want to do with it. My question is to anyone with a 2.5-3" lift running 285-70-17's. I plan on keeping the stock UCA for a while and want to make sure the 285's will clear them. I am pretty sure a wheel with 4.5" of back spacing would clear them fine as they do on 4th gen 4runners and FJC's, but the wheels I want only come with 4.75" backspacing (Eagle Alloys Series 012 - 17x9 -5mm/4.75BS). So the question is will 285's clear the stock UCA's on a wheel with 4.75" of backspace on a lifted GX? Any ideas?

Also, thanks to everyone for all the info and inspiration provided on this site. Coming from a semi-built lifted 3rd gen 4runner I am excited to get my hands on one of these V8 beasts!

 

[GXO]

I run 4.5" -10 on mine. I also have UCAs though. I think the offset is the key more than the BS to get that clearance. Stock has 0 offset so they let the hub and rim get waaay too close to the UCA. I was close even with UCAs on stock wheels.

 

[madtoy]

Stock wheels have 4.75 backspace (25mm offset). Without a spacer, they'll be all over the UCA. A wider wheel with the same backspace will give ever so slightly more clearance from the UCA - but we're talking millimeters, so it would still be all over it. You really need 4.5" backspace at max to clear, unless you want spacers (horrible idea unless you want to run stock wheels).

But I'll disagree with Dan (sorry Dan). Backspace is more important than offset - but wheel manufacturers give you only wheel width and offset, so you have to calculate the backspace on your own. you want something between 4" and 4.5" backspace. For example, an 8" wide wheel with 0 offset would be 4" backspace. An 8.5" wheel with 0 offset would be 4.25" backspace. An 8.5" wheel with -6 offset would have 4" backspace.

 

[GXO]

If you have a - offset it will ultimately drive the backspace as well. +25 stock vs -10 is a huge outward movement with the same backspacing. That was what I was saying.

 

[lobodog1]

Thanks guys, I was worried the eagle alloys with 4.75" backspacing wouldn't work. There are a few 4.5" backspaced wheels i have in mind. I just always look at a chart to figure the backspacing based off the wheel width and + or - offset.

 

[madtoy]

If you have a - offset it will ultimately drive the backspace as well. +25 stock vs -10 is a huge outward movement with the same backspacing. That was what I was saying.

Definitely. I would imagine lots of cab mount choppin' too.

 

[GXO]

correct, but I already did that too since my lift settled over the years and started to rub with 285s

 

[Living in the Past]

Instead of creating a new thread I'll ask here. Has anyone installed take offs from the LC250, GX550 or new 2025 4Runner on a fourth generation 4Runner?