How to remove (and replace) the drum from the older Whirlpool 29 inch dryer models :

Removing and replacing the drum of an older Whirlpool model
Note:
Disconnect the power source to your dryer before you begin to remove the drum. Either unplug the unit from the wall outlet, remove the appropriate fuse from the fuse box, or flip the appropriate breaker in the circuit breaker panel.

Pull your dryer out from the wall to avoid hitting the wall when you raise the cabinet top. Lift the lint screen access cover and remove the two screws inside. Do not remove the actual lint screen before you remove the screws. Removing the lint screen first could lead to accidentally dropping the screws down the lint screen shaft and into the blower wheel.

If your older Whirlpool clothes dryer model has a kickplate, remove it first. You can either pop it off, or pry the kickplate off the interior spring catches. Depending on your model, you may have to use a putty knife to push in on the spring catch at the center of the top of the kickplate. With the kickplate removed, proceed to lift the cabinet top.

Use a putty knife, or some other thin and flat object to wedge in under the cabinet top. Your goal is to push each of the two interior spring catches back out of the way, thereby releasing the cabinet top. The spring catches are located one on the left side under the cabinet top and one on the right side under the cabinet top.

If you have a kickplate model, you can now release the belt from the motor pinion. Push the idler pulley arm (also known as a belt tensioner) with your thumb to loosen it. Use the fingers of the same hand to slip the belt off the motor pinion. It your model does not have a kickplate, you will have to wait until the front panel is removed before you remove the belt from the motor pinion.

NOTE: Before you remove your dryer's front panel, remember that the front panel supports the front of your dryer's drum. Be extra cautious when removing the front panel to not drop the dryer drum.

Loosen the two bottom screws securing the front panel to the unit. Do not remove them just yet. Locate the two screws at the inside top of the cabinet. They also help to secure the front panel to the dryer unit. Remove these two screws. Balance the front panel and drum as best you can as you remove the two bottom screws that you have just loosened. Disconnect the wire leads connected to the door switch. Hold the dryer drum in place and remove the front panel of your dryer. Some models may have extra screws holding the front panel in place. If you are having difficulty removing the front panel, do a check for more screws.

If you have a kickplate model, you can slide your drum right out of your dryer because you have already removed the belt tension. The drum will slide right through the curved cutouts in the sides of the cabinet frame.

If you don't have a kickplate model, you will have to do your best to hold the dryer in place while you remove the belt tension as was previously described, before you can slide the drum out of the cabinet.

Reinstalling your dryer drum and reassembling the entire unit is basically the disassembly process in reverse. Though it can be a little tricky.

Place the belt around the drum before you put the drum back in its spot. Reach beneath the drum and make sure each of the two rollers are fitting into the groove at the back of the drum. If your dryer does not have a kickplate, line up and apply pressure to the belt before you begin to put on the front panel of the dryer.

With your dryer drum in place, check the belt to make sure it is lying flat on the drum. Line the belt up with belt skid mark on the drum. Apply tension to the belt by forming a loop with it that you slip under the tensioner (also known as an idler pulley arm), and then slip the belt loop around the motor pinion.

Reattach the front panel of the dryer in the same manner you took it off. Spin the drum around a couple of times by hand. Keep in mind that this may be a little difficult, as you have already reapplied tension to the belt. Pay close attention to the belt to make sure it is flat all the way around. Also check the rear seal to make sure it is not pinched around the drum anywhere. Make sure you reattach the wire leads to the door switch, and replace all of the screws that were earlier removed.