Tire size

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hapyspaz

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Okay guys. There are several factors at play here.

First off, 275/60R20 is 33"H X 10.8"W X 20"
I would go into tire sizes and try to explain it, but just use this website and bookmark it. Another good one that I like better is here.

Everyone needs to understand that tire size is not the only thing we have to look at though. Wheel offset is one of the biggest factors. If I remember correctly 2WD OBS Tahoes have a factory offset of +12; 4WD factory offset +25.

What does this mean? The larger the offset number the further it is going to suck the tire into the wheel well. For example, I have 18's off a 08 Silverado, that have a +31 offset, so the "center" of the wheel is 5mm closer to the outside of the wheel, moving the tire closer to the frame. This is why when looking at off-road wheels you will see a -25 or so offset, which moves the center of the wheel closer to the inside moving the tire out, hence the tires sticking out the sides of the fenders.

285/70/16 according to the Kumho website is equal to a '32 and is just shy of a '33. (32.8 if my memory serves me correctly)

31.8" actually

nodora96? What are your wheels off of? Are they factory take offs or an aftermarket?
 

TigerEyz3

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Okay guys. There are several factors at play here.

First off, 275/60R20 is 33"H X 10.8"W X 20"
I would go into tire sizes and try to explain it, but just use this website and bookmark it. Another good one that I like better is here.

Everyone needs to understand that tire size is not the only thing we have to look at though. Wheel offset is one of the biggest factors. If I remember correctly 2WD OBS Tahoes have a factory offset of +12; 4WD factory offset +25.

What does this mean? The larger the offset number the further it is going to suck the tire into the wheel well. For example, I have 18's off a 08 Silverado, that have a +31 offset, so the "center" of the wheel is 5mm closer to the outside of the wheel, moving the tire closer to the frame. This is why when looking at off-road wheels you will see a -25 or so offset, which moves the center of the wheel closer to the inside moving the tire out, hence the tires sticking out the sides of the fenders.

31.8" actually

nodora96? What are your wheels off of? Are they factory take offs or an aftermarket?
Well said... :Handshake:
Factory offset on my 2WD 4DR wheels (15x7) are -6.35mm with a 3.70" backspacing. Been running Torq-Thrust IIs for the longest (15x8 with -17.78mm offset and 3.75" backspacing) with tires ranging from 275/60 to 32x11.50.
 

IRQVET

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Okay guys. There are several factors at play here.

First off, 275/60R20 is 33"H X 10.8"W X 20"
I would go into tire sizes and try to explain it, but just use this website and bookmark it. Another good one that I like better is here.

Everyone needs to understand that tire size is not the only thing we have to look at though. Wheel offset is one of the biggest factors. If I remember correctly 2WD OBS Tahoes have a factory offset of +12; 4WD factory offset +25.

What does this mean? The larger the offset number the further it is going to suck the tire into the wheel well. For example, I have 18's off a 08 Silverado, that have a +31 offset, so the "center" of the wheel is 5mm closer to the outside of the wheel, moving the tire closer to the frame. This is why when looking at off-road wheels you will see a -25 or so offset, which moves the center of the wheel closer to the inside moving the tire out, hence the tires sticking out the sides of the fenders.



31.8" actually

nodora96? What are your wheels off of? Are they factory take offs or an aftermarket?

Thanks Austin for clearing that up somewhat, its still a bit confusing thou, but I have a little better handle on it now.

My Tahoe is 4WD and I purchased a set of 17 inch wheels that are sitting in my shed until I save enough cash for tires. I was under the impression that I should buy 285/70/17 from what I gathered from those here on this forum. When I saw the pictures above I got confused as hell. :emotions122:
 

hapyspaz

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They are off of a 2009 Nissan Armada!

Okay, so they have an offset of +20 on a 20 X 8 wheel. Not too much of a difference from factory, but they are an inch wider, so they are still sucked in on the inner sidewall.

Normally on this body style I have put +10 up to + 15, but normally have to crank the torsion bars to level the front end when putting 33" tires on.

You can probably get away with it if you crank the front up about an inch.
 

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