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Tire Choices for 20" Rims

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2012 oil change interval

2015 Mudflaps

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I'm looking at trading my 2009 2500 for a used 2015 2500 with the 20" rims. The choices for tires seems very limited. I've only found one set of Michelins, Goodyear Duratrac, and the Firestones that were factory options. I'm looking for an AT tire and was hoping to get the BFG AT KO2, but no go. Any brands that I am missing?
 
The Duratrac is one of the better brands you will find. I'm very impressed with mine. 275/65 R20 are slightly taller, slightly narrower and a whole lot cheaper than the 285/60 R20 that the truck comes with.
 
I don't understand why you say the BFG AT KO2 is a 'no go'? I have the original version of that tire on my 20' wheels.
 
Thanks for the input so far. Ideally, I would like to stick with the original size.

I have already looked at the Tire rack and several websites for the different companies as suggested.

I'll have to look at some other sizes that are close to the same diameter as the 285/60 like some of you have done.

Can alternate sizes be programmed into the truck computer to compensate for different sizes?

The OE Firestones are a lot cheaper than any of the other tires, but nobody seems to get much for mileage out of them.
 
The tires I listed above are only slightly more than 1/2" larger than stock, but my speedo is dead on with my phone GPS. With that said, my wheels and tires were installed by the dealer, perhaps they reprogrammed it when they modified it? Regardless, it is a very small difference.

But yes, they can reprogram the PCM for tire sizes.

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The formulas to determine the dimensions of standard sizes are below. Actual tires may vary.

Section Width = Given on the tire in millimeters, simply convert to inches.
LT285/60R20 = 285mm / 25.4 = 11.2 in

Sidewall Height = Aspect Ratio x Section Width / 100.
LT285/60R20 = 60 * 11.2 / 100 = 6.7 in

Total Diameter = Rim Diameter + 2 * Sidewall Height
LT285/60R20 = 20 + 2 * 6.7 = 33.5 in

For size LT295/60R20
Cross Section = 11.6 in
Diameter = 33.9 in
If your speedometer was dead on with the stock tires, at 70 mph your speedometer will now read 69. Even with stock tires, tire pressure and tire wear will affect it by more than that. No need to adjust the computer for this slight change in size.
 
DThiel, that makes sense. I don't think the BFG's are in the 285 size. I have 275/65's that I ran on my 2012 and still have them. My current 2015 came with the 285 Firestone's, but I personally don't like them that wide.
 
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