Tires: Light truck tire inflation, truck tire inflation, goodyear wrangler silentarmor

Question
The OEM tires on my 1994 Chevrolet K-1500  "Work Truck"regular cab long bed 4x4 V-6 manual transmission truck with heavy-duty chassis were 225/75R16 standard load Goodyear Wrangler on/off road tires on standard 7x16" steel wheels.  Mfrs recommended inflation is 50 psi, which equates to 1765 pounds of load capacity per wheel.  I have replaced the aged OEM tires with new Goodyear Wrangler "SilentArmor" 265/75R16 Load Range E service rating 123/120R.  Most truck miles are zero to light load at 55-75 mph on the highway.  Should I inflate to 35 psi because that matches the load capacity of the OEM tire at 50 psi (1765 pounds per wheel), or to 50 psi because that matches the OEM inflation recommendation?  Whatever your answer, why?

Answer
Harry,

There are a couple of things I need to clarify.

The load carrying capacity of an LT225/75R16 at 50 psi is 1765 # for a dual application and 1910 # for a single wheel application.  Obviously a K1500 is a single wheel.

But you are pretty close about the load carrying capacity - I actually got 36 psi, but that's minor.

You should match the load carrying capacity, not the pressure.

Obviously we would want the footprint of the tire to be about the same, and matching the load does that.

However, the spring rate of the tire is a function of inflation pressure, and matching the pressure would more closely match the spring rate.  But by comparison, the spring rate is not nearly as important as the footprint.