Diesel LOVES digging! He is a mucky pup with a love for mud and getting up to mischief. He may not be the smartest pup, but Diesel has an amazing sense of smell which he can use to help get the pups out of trouble!
Role in the series
Diesel's first prominent appearance is in "Muddy Pups", where he interrupts Dylan, who is in the middle of cleaning the floors. Angered by Diesel making a mess of the place, Dylan attempts to clean Diesel, but the messy pup begins digging again, causing to Dylan to pass out and have a nightmare about Diesel's digging. When Dylan awakens, thanks to Diesel's licking, he finds the floor is clean again, but Dylan accidentally knocks over the water bucket in the process.
Diesel shakes himself dry, with Dylan joining him.
Diesel also makes a brief appearance in "Boom Night", where his ear protectors are covering his eyes, causing him to walk in to the wall until Dylan adjusts them, before later jumping out on Dylan to announce "BOOM TIME", as Dylan is getting the pups ready for the night in question. He is then seen, with the other Pups, watching the Fire Works.
Diesel plays a prominent role in "Power to the Puppies", where Dolly and Dylan call a snap election to decide who Top Dog is. Diesel comes in during a debate (whoever maxes the Wag-O-meter first becomes Top Dog), and mishears Dylan saying "Top Dog" as "Hot Dog" and refers to treats. This gets the other pups excited and maxes the Wag-O-Meter, making Diesel Top Dog much to Dolly and Dylan's shock. Diesel quickly becomes overwhelmed and Dolly offers to run the place while he digs. The house falls in to disarray, and the pups shall only listen to Diesel as he is the Top Dog. Dolly tries to tell Diesel that he needs to get the other pups working together, but Diesel does this by telling the other pups to dig the deepest hole they can, which causes the pups to hit a water pipe quickly flooding the house. Dylan organizes a plan where Dolly turns the water off at the mains, while Diesel digs back down to the broken pipe to plug it with a chew toy. Dolly and Dylan ask if they can be Top Dogs again, which Diesel agrees to while also helping clean the place up before Delilah and Doug get home.
In "Winter Funderland", when Dolly makes the House a Snow Party, Diesel is seen digging through the Snow and licking the ices, before getting his tongue stuck to the ice.
In "Snow Day", Diesel is the first one to notice how Dorothy was able to get out of the house, and helps Dolly, Dylan, Delilah and Doug search for her, using his nose. He thinks that he found her at one point, and tries to chase her tail about a lamp post, not realizing he is chasing his own tail.
In "Poetry Scam", his right leg had to be bandaged and he had to wear a cone because of his habit of biting on the bandage. The cone allows him to pick up random nearby voices of animals (only the cases with Pearl and Clarissa were shown on-screen). As he mimics what the animal is saying, his head morphs into the shape of said animal's head. Dolly and Dylan decide to take his cone and put it on Dolly so that she can receive Dylan's poems as there wasn't enough time to teach her any. While this was happening, Diesel had to be accompanied by Dylan to prevent him from chewing on his bandaged leg.
He made a cameo appearance in "Crushed Out" at the dinner table witnessing Dylan's gothic makeover.
In "Girls' Day Out", he was part of a puppy tower that Dolly used to get to the window of Delilah's room. When the tower fell and everyone was on the ground, he began chasing his tail.
- According to Dawkins, Diesel requires extra vitamins in his kibble.