I kinda like hush-puppy. It uses the Hushpower name kinda, it's deceptively cute, and because it's a new thing in the monster truck scene and new things are often called young pups, it works well.
Hush Up would be my second choice.
Namely, because it makes me think of slush puppies, which are GREAT. Not to mention, isn't a hush puppy some odd southern food? As if anything is more southern than diesel and monster trucks...Good fit.
Black Magic, Hush-Hour, Not so "Hush" Power (get it, cuz that sucker is loud!) Paint it white and call it the Vanilla Gorilla! Straight Line ( inline 6), Pure Diesel Power (got to talk to garret about that one),