Removing the rear brake drums on your Toyota Sienna is the only way to inspect or replace the shoes inside the drum or inspect the drum for wear and damage. The rear brakes do not wear as quickly as the front brakes but they should not be ignored. Brake shoes that are neglected can scar the brake drums, causing damage that will require replacement of the drums over time. If the drums are in need of replacement, most auto parts stores carry aftermarket replacement drums and OE replacements are readily available from any Toyota dealer.
Loosen the lug nuts on the rear wheel studs of your Sienna with a lug wrench but do not remove them from the wheel studs. Place a jack under the rear of the van and raise it until the tires are about two inches off the ground.2
Place a set of jack stands under the rear suspension of the van then lower the jack, allowing the van to settle onto the jack stands. Remove the lug nuts from the wheel studs then remove the wheels and tires from the rear of the van.3
Locate the inspection hole on the rear of the brake drum and insert a small flat screwdriver into the hole. Slide the screwdriver in between the adjuster tab and the adjuster inside the drum then slide a brake spoon into the hole and turn the adjuster down, loosening the brake shoes.4
Move to the front of the drum and check the base of the wheel studs for drum retaining rings. If the rings are still in place, remove them by prying them off with a flat-head screwdriver and discard them. They may have been already removed if the rear drums have been previously removed from the van.5
Grasp the drum on either side and slide it straight off the brake shoes. Set the drum aside and move to the opposite side of the car, repeating the process to remove the second drum.