Rails

Personality:

Rails is a big fan of trains, he even drives a real one himself as the Train driver of Happy Tree Railroads, he collects model trains and loves to display them all around his home, he adores his job and never grows tired of it, always happy to take owheres where they needed to go, he speaks in a pretty muscular voice like Pop

Trivia: His working name was Chuchu.

He may have been the driver that ran over Handy, Lifty and Shifty in Don't Yank My Chain, but this is unclear.