Tires: load rating, gsa auction, tire guides

Question
I HAVE A 2001 2500 4WD DODGE TRUCK WITH A SERVICE BODY I BOUGHT IT OFF A GSA AUCTION . THE FRONT TIRES & BACK TIRES ARE DIFFERENT . THEY HAVE TWO DIFFERENT LOAD RANGES C & E .WHAT LOAD RANGE DO I NEED WHEN I GO TO REPLACE THEM.I HAUL LOADS & PULL LOADS WITH THIS TRUCK & I WANT IT RIGHT. ITS NOT A DUAL WHEEL.WHAT DO THE RATINGS MEAN ANY HOW ? THANKS

Answer
Tyler,

The first step in this should be for you to find the vehicle placard - which lists the original tire size (including the load range) and the proper pressure for that size.

Load range is a way of expressing the load carrying capacity of a tire for tires that have the same physical dimensions.  For example:  An ST225/75R15 LR C has a load carrying capacity of 2150 # at 50 psi, while a LR D is 2540 # at 65 psi.  Notice that the higher load range also allows more pressure (so the tire can carry more load).

If Tire Guides is right, the tire size ought to be either LT245/75R16 LR E or LT265/75R16 LR E.  Note that both of these are LR E.  I am going to guess the placard shows the LT265's - and if that is the case, this means the front tires don't have enough load carrying capacity for use on the rears, but are OK for the front.  This is obviously not a situation where you can rotate tires and I'll bet some "smart" bureaucrat figured out a way to save a few bucks while making life more difficult for the mechanic.