Tires: alternative tires, inflation pressure, tire placard

Question
Can a new set of 4 LT 265/75/R16 tires be put on a Suburban that calls for  P 265/70/R16 tires or in other words can tires with an aspect ratio of 75 be substituted for tires with an aspect ratio of 70 as long as all 4 tires are the same?

Answer
John,

First, I am not a fan of replacing P type tires with LT type tires - and in a moment you'll see why.

In order to carry the same load a P265/70R16 does at 35 psi - the pressure specified by GM on the vehicle tire placard, an LT246/75R16 needs to use 50 psi.  The suspension was designed for a tire with a certain spring rate - and spring rate is pretty much tied to inflation pressure regardless of who makes the tire.

So I do not recommend switching P's for LT's