A disk drive is disclosed comprising a disk having servo data defining a plurality of servo tracks. The servo data comprises a preamble, and a plurality of slanted line servo bursts recorded at a tilt angle with respect to the preamble. The slanted line servo bursts comprises a first plurality of slanted line servo bursts and a second plurality of slanted line servo bursts, wherein the second plurality of slanted line servo bursts are offset radially from the first plurality of slanted line servo bursts. A position error signal (PES) is generated in response to a phase difference when reading the preamble and the slanted line servo bursts.