I HAVE A 99" PSD 4X4 F350 WITH THE 5200LB FRONT END
(SNOW PLOW PKG) I JUST INSTALLED TIRES 305X70 X16
THE TRUCK SETS A LITTLE LOWER THAN BEFORE WITH THE FACTORY 265/75'S
I'M PLANNING ON ADDING A 3/4" STEEL PLATE UNDER THE FRONT LEAF SPRINGS, WILL THIS CAUSE A PROBLEM?????HELP???

 

It certainly could, you should never add anything between the front springs and axle, to much side to side tourqe when turnning.
Perhaps a leveling kit would be the way to go.