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18 inch tires on 17 inch stock alloy rims?

guttersnipes199

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Hi, will 18 inch tires fit on my 17 inch stock alloy rims? I have a 2003 1500 z71 avalanche with body cladding?

Thank you for any info you can provide!
 

Vaeagleav

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Quick answer : NO you need to match 18" tires onto 18" rims.
 

guttersnipes199

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Thanks so much again! For the same 2003 z71 with cladding, Would there be a 17 inch tire size with a higher sidewall than the 265/70R17, that would fit on the oem alloy rim without modification, and not rub or decrease the turning radius? Thanks for any info you can provide!

 

SRFNSNO

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https://tire-calc.com
if you go up to 285/70-17 you will increase tire Dia by 1.1"
on clad AV going + tire size you may need to trim front and also level AV.

My $0.02 :B:
 

Vaeagleav

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Just remember if you change overall diameter of tires then you may throw off you odometer and speedometer and have to recalibrate them.
 

guttersnipes199

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Ok, so I'm gonna stay with the oem size 265/70r17. I was looking at the Falken Wildpeak AT3W all_ Terrain Radial Tire-265/70R17 115T. Will this be appropriate for the 2003 avalanche z71? Because there is also the Falken Wildpeak AT3W all_ Terrain Radial Tire-265/70R17 121S, which is more expensive. Will the 115T be sufficient?
 

BainMan

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Borrowed this from an Amazon review... He/she sounds knowledgeable, and is correct about the ply ratings, so I'm going to parrot it here:

"The 115T signifies that the tire has a 4ply standard load sidewall. The 121S signifies a 10 ply load range E sidewall. The standard load tire is best for a half ton truck, whereas the load range E sidewall is best for a 3/4 and 1 ton truck."

So in short, yes you will be fine and should choose the 115T.

** Please note you are obligated to post pictures of the new tires after you get them installed!
 

ygmn

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tire rack explains all the tire lingo

https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=35

Those numbers mean Load rating
115 = 2679lbs
121 = 3197lbs

Letter is speed rating:
S = 112mph
T = 118mph

Ensure both are equal to or greater then stock OEM.

Read tire rack great explanations
 

lunchwagon

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I just bought those tires in the 4-ply version, and very happy with them so far. 

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