How do you replace the drive belt on a john deere LA125?

To replace the drive belt on a JOHN DEERe LA125, first, ensure the mower is turned off and the key is removed. Raise the mower deck and remove the mower deck by disconnecting the belts and any retaining pins. Then, locate the drive belt and remove it from the pulleys, replacing it with a new belt and ensuring it is routed correctly according to the diagram in the owner's manual. Finally, reassemble the mower deck and adjust the tension as needed before testing.