A disk drive includes a storage disk having a data surface, a head suspension assembly, an actuator assembly and an E-block. The actuator assembly moves the E-block relative to the storage disk. The E-block includes a first actuator arm and a second actuator arm. The first actuator arm supports the head suspension assembly while the second actuator arm supports no head suspension assemblies. The first actuator arm has a first upper surface having a first configuration. The second actuator arm has a second upper surface having a second configuration that is different than the first configuration and is tuned to decrease off-track displacement of the data transducer. In non-exclusive alternative embodiments, the actuator arms have substantially similar thicknesses, but have different perimeters, shapes, volumes and/or other properties.