265/60/20 to 275/60/20 why gm did this ?

[Big_Kahuna]

so the at4 come from the factory with 3  different size tires  275/65/18 265/60/20 and 275/60/20 , what I don't understand is why gm put different size tires for the all terrane tire what is 275/60 /20  and mud terrane they put 265/60/20 WHY ??

[calgator73]

9 hours ago, Big_Kahuna said:

so the at4 come from the factory with 3  different size tires  275/65/18 265/60/20 and 275/60/20 , what I don't understand is why gm put different size tires for the all terrane tire what is 275/60 /20  and mud terrane they put 265/60/20 WHY ??

Unless they have really changed things up you get a factory choice between an LT275/65/18C MT and a 275/60/20 AT.  That's why you have those two choices? I guess the answers come down to style preference and capability desired. Those mud terrains are really good but loud and the all-terrains provide a really good balance and are very quiet.  Also the 18s are a 32-in tire and the 20 is a 33-in tire.

Edited November 25, 2022 by calgator73

[Big_Kahuna]

3 hours ago, calgator73 said:

Unless they have really changed things up you get a factory choice between an LT275/65/18C MT and a 275/60/20 AT.  That's why you have those two choices? I guess the answers come down to style preference and capability desired. Those mud terrains are really good but loud and the all-terrains provide a really good balance and are very quiet.  Also the 18s are a 32-in tire and the 20 is a 33-in tire.

I dont understand why thy put the 265 ?I did look at the tire specs and said that those particular  tires are 32.8 inch tall  so im thinking they are close enough to 275 AT what are 33 inch....

[Diamond817]

1 hour ago, Big_Kahuna said:

I dont understand why thy put the 265 ?I did look at the tire specs and said that those particular  tires are 32.8 inch tall  so im thinking they are close enough to 275 AT what are 33 inch....

I believe it is because the tire they use (Goodyear Territory MT) is only available in 265 and not 275.

 

 

 

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Edited November 25, 2022 by Diamond817

[f8l vnm]

GM wussed out on tire size for the ZR2 and AT4X. Period.  We can use any other word but to charge premium money and not even give it 35s is a disappointment. Heck I think the new Colorado ZR2 comes with same size now as well. 

[swathdiver]

On 11/24/2022 at 8:55 PM, Big_Kahuna said:

so the at4 come from the factory with 3  different size tires  275/65/18 265/60/20 and 275/60/20 , what I don't understand is why gm put different size tires for the all terrane tire what is 275/60 /20  and mud terrane they put 265/60/20 WHY ??

 

Because the larger size is not needed with the MT to get through the terrain it was designed/intended to traverse.

[KARNUT]

I’m just spitballing. How about it’s a gas milage considering? I imagine everything gets thrown into a pot for overall gas mileage. Considering what they went through with cylinder deactivation. Just to gain 1-2 miles per gallon. They finally said that’s all they achieved on their window sticker. With the chip shortage and their 50$ discount when they couldn’t turn it on. With GM it could be that simple. I never gave much thought to original equipment tires. I put KOs on and went with those.

[Big_Kahuna]

so I put 275 60 20 what are .5 inch taller and I was thinking my speedo will be off but than I download gps and the speedo I right on.