Some time in late 1969(?) or 1970, DC comics and ABC created product tie-in comic books and cartoon episodes based on the famous and very popular Mattel toys.
Rumor has it that the cartoon was canceled because it was not much more than a 1/2 hour commercial. As we know Toth designed the characters and created some of his best comic book art in the DC comic book.
Here is the Hotwheels Cartoon opening theme and some small scans of some Toth Newspaper Comic Strip Ads.
Unfortunately not much Toth art in the opening theme bit. It's more like a commercial than an opening theme. If this opening is any indication of the show, I can see why in the "dark ages" of TV that they had some issues with it. Now of course everything is a big product blur; practically every cartoon has toys and vice-versa.
It would be nice to see an episode of this cartoon. IMDB details for the show.
Also as a special bonus, the Mostly Ghostly Music Sharing Blaaahhhggg!!! has a download link to the ghastly tie-in album (which includes the Skyhawks cartoon theme). Who knew they had music too?