Ghost_man,
Though we discuss various thngs here at the Ulysses mod forums, which we have a 'Off Topic' forum for, we don't support other mods that we haven't made, unless someone is modifying them to work with the ULib/ULX functionality.
Please search the Garry's Mod forums at
http://forums.facepunchstudios.com, probably in Mods/Releases, for help with your question.
There are three I can think of that use cars.
But, as I don't pay too close of attention, please see this list, and click the link to the post that supports the mod you downloaded.
http://forums.facepunchstudios.com/showthread.php?t=244324