A GM mechanic said that the lack of the transmission from shifting out of 2nd gear is most likley is the result of apple coring of the "Reluctor drive shaft Gear" which in turn prevents the speed sensor from picking up any rotation thus preventing the vehicle from shifting gears.

The speed sensor detects the rotation of a gear like device that is mounted to the reluctor drive shaft which rotates within the enclosed speed sensor housing.

Does that sound correct? I will have to take off the speed sensor and remove the reluctor drive shaft in order to inspect the gear to see if it has apple coring.

Does the speed work?