Tl* the contact owns a 2019 toyota 4runner. while driving 65 mph, a high-pitched whining noise was heard from the rear axle. each time the accelerator pedal was depressed, the whining noise occurred. when the accelerator pedal was released, the whining noise went away. the vehicle was taken to big two toyota of chandler (located at 1250 s gilbert rd, chandler, az 85286, (480) 989-6000) where it was test driven. the technician informed the contact that it sounded like the pinion gear was not assembled properly. the contact asked why the whining noise only occurred when depressing the accelerator pedal and was informed that it was due to the torque being applied. the vehicle was not repaired. the manufacturer was notified of the failure and provided case number: 1904182303. the approximate failure mileage was 5,300.