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  #13  
Old 06-01-2016, 08:50 AM
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Re: Help with wheels/tires

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Originally Posted by LJS8510 View Post
Those should fit with QL, but this size may not fit in the spare tire hole.
This is a good read concerning spare size-
What is the largest tire I can get on a WK2 Overland w/ 20" rims and QL? I really lik
From what I'm reading on these forums it's the people worth QL that have the minor rubbing issues in this size tire, for some reason. I have the standards suspension so hopefully I'm in the clear

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  #14  
Old 06-01-2016, 08:58 AM
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Re: Help with wheels/tires

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Originally Posted by Anthony31188 View Post
From what I'm reading on these forums it's the people worth QL that have the minor rubbing issues in this size tire, for some reason. I have the standards suspension so hopefully I'm in the clear
I think thats correct, I have QL with very minor rubbing.
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  #15  
Old 06-01-2016, 09:06 AM
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Re: Help with wheels/tires

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Originally Posted by Anthony31188 View Post
.... I admit that me trying to wrap my head around how the sizing works and what the numbers mean was quite interesting....
I'll break it down for you. There are two different "sizes", P-metric and SAE. SAE is easy, it says what it is. For example 35x12.5R17. That's a 35" diameter tire, that's 12.5" wide on a 17" rim.
The numbers people have difficulty understnading are the P-metic sizes. They're not that bad once you know what they mean.
To use an example, I'll use the 275/55/20 that you ordered. The first number is the width of the tire in millimeters. So the tire you ordered is 275mm wide (or 10.8").
The second number is the aspect ratio. What that means is it's the percentage of the width to the sidewall. That's the confusing part for most people, but I'll try to simplify. On your tire, that is 55%. So to calculate the sidewall, you take the width (275) and multiply by .55 (or 55%). That gives you 151.2mm side wall height (or 5.9"). Why do you care about the side wall? This allows you to calculate the diameter of the tire. Keep reading.
The last number is the rim diameter. Oh, but wait for it...... it's in INCHES. Stupidest thing ever. Metric width, percentage, and SAE rim. No wonder it confuses people. Whatever, moving on. In the example you've got a 20" rim, so that number is 20. Pretty easy one there.
Back to calculating that diameter. Take that sidewall height we solved for earlier, and double it. Why? Because there is sidewall on both sides of the rim. So 151.2 x 2 = 302.4 (or 11.9"). If you did the calculation with the 5.9" I posted earlier you'll come up with 11.8". Don't freak out about it, it's just due to rounding to 1 place rather than further out. Anyway. You then take that 11.9, and add it to the rim diameter of 20, for a total tire diameter of 31.9".
So to put it all together. A 275/55/20 is 10.8" wide, by 31.9" diameter on a 20 inch rim. In a SAE size this would be considered a 32x11R20.
Hopefully those tire sizes make a little more sense now. Just remember the bigger the first number, the wider the tire. The smaller the second number the lower profile the tire (smaller side wall). One thing to consider with that second number though is it doesn't always mean a bigger number is equal to a bigger diameter tire. Keep in mind it is affected by the first number and rim diameter (you'll see this further down when I mention the spare tire).


Quote:
Originally Posted by Anthony31188 View Post
... I definitely like the look at the "meatier" off road tires
I agree. I've sold the 20's off my Rams to put beefier 17" tires on them. This gives you more side wall (which usually looks beefier) while keeping the same tire diameter. Add that to a more aggressive tread and it usually looks pretty tough. I'm considering doing the same on my Jeep.

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Originally Posted by Anthony31188 View Post
....And the spare totally slipped my mind lmao. I'll have to get on that. Derp. Will it be sufficient as is to just put on if I get a flat and get me to a tire shop? I know the ride won't be nice but will it do the job?

Hopefully they get on with no issues.
I wouldn't drive more than a few feet to get off the road with a mismatched size like that. The size you're upgrading your tires to is 32", while the stock tires/spare are roughly 30". If you drive any significant distances with a tire that is 1.5 - 2 inches smaller you're going to risk messing the LSD, and/or transfer case/gears up. Basically you're forcing that one tire to spin faster than the rest. The circumference of the smaller diameter tire causes it to cover less ground than the bigger tires with each revolution. Since they're all going the same actual distance, the smaller spare, would have to rotate faster to keep up. Not a good thing to do for any amount of time. No big deal to get it off the road, but I certainly wouldn't do it to drive to the shop, home, etc.
If you want to match the spare to the tires you're getting, you can buy a 255/70/18 and mount it on the stock spare rim. The rims size on the spare makes no difference as long as the tire diameter matches up.

Quote:
Originally Posted by Anthony31188 View Post
...... I ended up ordering Goodyear duratracs still in size 275/55/20, after a bunch of Memorial Day rebates I got all four for $620 so seemed like a good deal for a slightly higher quality tire.....
I had a set of Duratrac tires on my '07 Ram. Great tires. I'd go as far as to say they were the favorite off road tire I've had so far. I had a different size but they should perform the same. And at $620, that's a smoking deal for them.
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Old 06-03-2016, 02:30 PM
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Re: Help with wheels/tires

Thanks everyone that helped or commented. Wheels and tires went on today. 275/55/20 fits like a glove, no rubbing at all. Very happy


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  #17  
Old 06-03-2016, 02:55 PM
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Re: Help with wheels/tires

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Originally Posted by Anthony31188 View Post
Thanks everyone that helped or commented. Wheels and tires went on today. 275/55/20 fits like a glove, no rubbing at all.
Those things look BA! Congrats.
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  #18  
Old 06-03-2016, 04:19 PM
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Re: Help with wheels/tires

Looks great - love the spider monkeys and duratracs!


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Old 06-03-2016, 04:49 PM
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Re: Help with wheels/tires

Thanks guys!
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