Firehouse Tales is a cartoon produced by Warner Brothers Animation that ran from 2005 to 2006. It aired on Cartoon Network in the U.S., and their sister service, Cartoonito in the U.K. and Europe. It is about a trio of firetrucks named Red, Crabby, and Petrol. This show wasn't treated well by Cartoon Network due to low ratings, and hasn't been seen in the U.S. since at least 2007, but it was airing in Europe until September 2014. This show never had a DVD release, and it isn't known to have been available on Netflix, iTunes, or Amazon Instant Video either, and also, only one episode is available in it's original English on the internet, but there are some more episodes of it in Hungarian, (European) Spanish and (European) Portuguese.
Update - 9/4/2016 - The episode "Petrol's Paint Job" (the opening is missing, because at the time, Cartoon Network in the UK would usually skip the theme song on a lot of their shows) has been uploaded by Lastofthetimelordz, and it is possible that he can upload more. https://www.youtube.com/watch?v=g84AmM_fVAk