The Flumadiddle is a car built by Grandpa Doc and appeared in "Grampa Grumpy and the Ogre." Grandpas Grumpy and Happy and their grandsons use the vehicle to find the ogre who steals a coveted gem from their retirement home. The Flumadiddle will reappear in the episode "A Royal Pain in the Castle".
The Flumadiddle is a wooden ATV; on its ends are a modified barrel with the steering wheel (on the front) and a bucket with a handle (on its rear) to provide seating and cargo. There are two doors and two tires on each side. A lantern is used as its headlight. A hand crank is used to power up. The Flumadiddle is built for any kind of terrain it travels on -- it can transform to a swamp buggy, a boat (an anchor replaces the lantern in this mode), and aircraft (in this mode the propeller, goggles, and wings appear). It is powered by a crank.
In the show
Happy and Grumpy and their grandfathers borrowed the Flumadiddle from Grandpa Doc to search for the ogre. Once they leave the garage, Grandpa Happy is driving it too fast, causing Grumpy and his grandpa to fall out. Grandpa Grumpy then took the steering wheel; this time they're traveling slowly and then they barely went into a pond. Later, they drove into the swamp, and the Flumadiddle transformed into a swamp buggy with inflatable tires. The gang thought they spotted tyhe ogre but it was actually an alligator, and they began to attack. The dwarfs eluded them as fast as they could, and the swamp buggy Flumadiddle becomes a sail boat.
While on the river, the dwarfs decided to fish for the ogre using candy corn they've brought along as bait. Grumpy gets nearly swallowed by a giant fish, and after Grumpy gets out of its mouth and throws it back, the force of the water moves the boat further downstream into a waterfall. The Flumadiddle is now a plane and the dwarfs are able to fly before they hit the water below. They fly into the mountains where they find the ogre and persuade him to return to them their belongings.