The John Deere 455 garden tractor uses hydraulic lift and shaft drive for its three optional mower decks.The deck removal process is the same, regardless of which deck is on your machine. The process requires no tools, but has a couple of steps where access is challenging and requires a bit of patience. A hard flat surface, like a concrete garage floor or driveway makes the job much less challenging than working on the lawn.
Turn the rear anti-scalp wheels 90 degrees from normal operating position and set them at their highest operating position.
Lower the deck completely. Remember, you probably have the deck limit set for your desired mowing height, which will not let the deck all the way down. Raise the deck slightly, then turn the deck limit control fully counter-clockwise, then lower the deck.
Pull the locking pin on the left side of the front draft arm and rotate the front draft arm forward. Lift the front draft arm out of the two hooks on the front of the mower deck and remove it from the work area.
Pull the spring loaded locking pins that secure the two lift arms to the mower deck and turn them so that they do not reengage. The deck is now free from the tractor's lift system, but it is still connected to the drive train.
Start the tractor and raise the mower deck lift arms to their highest position. Turn the deck limit control fully clockwise to lock the arms in their raised position. While the tractor is still running, turn the steering wheel to the left until you reach the limit of the wheels' travel. Turn the tractor off.
Raise the front end of the tractor and secure it on jack stands if you have the optional floor jack and jack stands. If you don't have an adequate jack and jack stands, the next step will be more difficult, but not impossible.
Slide the deck forward until the drive shaft front and back half separate from each other. Then work the deck out toward the left side of the tractor. If you do not have the tractor front end raised, this can be awkward. It can be done, but requires manipulating the steering wheel a time or two to create clearance for the deck as it is coming out. It may also prove necessary to disconnect the PTO drive line from the tractor before sliding the deck out if you don't have the front end elevated.
Grab the collar on auto-lock yoke of the drive shaft where it attaches to the tractor's mid-PTO shaft and pull the collar and the yoke toward the front of the tractor. The yoke should come off the drive shaft relatively easily, unless the deck has been on the tractor without being removed for a very long time. Penetrating oil and patience may be required for this step if that is the case. Once the drive shaft is removed. The process is complete.