Tire size help.

[Blazed]

My moms friend has a z71 tahoe and he has a lift on it but doesnt know how much it is his measurements are F38.68 and R40.18. What is the biggest tire he can run?

 

[Blazed]

Come on guys

 

[MSBlackZ]

For sure 275/65/18 and probably 285/65/18

 

[Blazed]

He's looking to run 305 or 12.5

 

[Zed 71]

My moms friend has a z71 tahoe and he has a lift on it but doesnt know how much it is his measurements are F38.68 and R40.18. What is the biggest tire he can run?

I will measure mine when I get back from travel next week. But just from memory, my front was close to 40" with a 2.5" front level kit. The rear was a little higher with 1" rear spacer and air bags.

He's looking to run 305 or 12.5

Just to give you an idea, I have 285/65/18s and had to trim a good 2 inches from the front valence caps. Running 305s will require more trimming than that.