Is your mechanic cheating?

Five out of nine Jiffy Lube repair shops were caught charging for parts, service, and repairs that were never completed.

Holly cow! I've heard of this happening but now, in an undercover investigation, news station KNBC Channel 4 has it on tape.

What didn't they do? Everything from not changing fuel filters to not changing transmission fluid—which is supposed to be completed using a special machine called T-tech. But they still charged big bucks for it.

Talk about a supreme rip-off. Heck, a district manager, Steven Aube (sp?), even went so far as to lie directly to the camera about his identity -- saying he was a customer. And Jiffy Lube wouldn't comment on camera saying it wasn't to their benefit.

Now think about how much money they're potentially pocketing from such unethical business practices—the Jiffy Lube chain services over 30 million customers a year!

Locations that were invloved included Encino, Canoga Park, Sherman Oaks, Glendale, and Burbank. All in the greater Los Angeles, CA area.

Watch the full news video.