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 re-engage. 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 driveshaft 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 driveshaft 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 driveshaft 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 driveshaft is removed. The process is complete.
The documentation for this process from John Deere is in the owner's manual for the mower deck, which is a separate publication from the tractor owner's manual. If you don't have the manual, it is available for purchase from any John Deere dealer. The front draft arm and the driveshaft can easily become separated from the mower deck while in storage. If you use a couple of plastic cable ties to secure them to the deck, they'll be there for you when it is time to put the deck back on. When reinstalling the deck, the most awkward step is putting the driveshaft yoke onto the tractor's mid-PTO shaft. You have to pull the auto-lock collar back while sliding the yoke forward at the same time that you're making sure that the splines line up. As with the deck removal, this process goes much smoother if you have the front end of the tractor elevated and safely secured.
If you raise the front end of the tractor for this job, use jack stands with an adequate rating for the tractor and make sure that the tractor is stable on the jack stands before attempting to remove the deck. Do not work under or around any piece of equipment supported only by a jack.