Tires: Non OEM Tire Size, proper inflation pressure, stock rims

Question
I have an 05 f250 4x4 with stock rims.  The stock tires are 265/70/17 load E . I am considering installing 285/70/17 load D tires on it only because BFG doesn't make a load range e in this taller size. The truck is used to tow a trailer "7000lbs" about 200 miles once a week plus normal highway use. Can I get by with this tire change.  

Answer
Tom,

Please check the placard on your vehicle to be sure what I am about to write is correct.  The placard is located on the driver's doorpost.

My book says that placard will say the proper inflation pressure is 70 psi front / 75 psi rear.  That means the tires were set to carry 3005 # front and 3100# rear.

An LT285/70R17 LR D has a maximum load carrying capacity of 3195 # at 65 psi.  That means it has enough load carrying capacity and to get the equivalent capacity as the original tire size, the pressure should be set at 59 psi front / 62 psi rear

BTW the stock rims should be 7.5" and that is the minimum rim width for an LT285/70R17.