Sometimes you take the lid off a topic and find that you have opened an unexpected can of worms.

The response was overwhelming to my column last week about my honest auto mechanic, John, who found that as an independent mechanic, he could not compete with the ever-increasing competition from car dealership repair shops. Among the auto repair rip-off horror stories and the auto mechanic recommendations I received from readers, there was one letter that stopped me in my tracks.

It was from a reader who signed his e-mail with only one name -- Bill. Bill's correspondence described to me a murky world that few outsiders have ever been privy to. He outlined the unscrupulous details of his experiences as a mechanic for unethical repair shops.

Of course, Bill can only describe the practices of the establishments he worked for. Certainly, every business has its own policies and procedures, and not all can be lumped into the same unsavory stew. With that in mind, let's consider the information that Bill imparts. It's food for thought: "I am now retired, but when I worked as a mechanic at large repair shops, we were told not to make problems when we were checking out vehicles, but we were told to find problems. Then we were told to be sure to 'talk up' what the damage could be to the customer's car if the problems we found were not taken care of."

"There was a kickback from whatever work we recommended that the customer had done. However, most of the money from this kickback was given to the mechanic in charge at the shop. If people came in for a 'checkup' and we told the shop foreman that we found nothing wrong with the car, he told us to look again and try to find something."

"There were many times when I saw other mechanics doing shady things -- like not doing required maintenance when they were supposed to. This was because usually we were forced to work on two or three cars at a time because someone else had promised that the cars would be done."

"And while the labor rate was high, we were only paid a small portion of that rate; the shop got the rest."

"I just wanted to say that you had a legitimate complaint when you wrote about trying to find an honest mechanic." -- Bill.

I don't know about you, but from now on, if I take my car into a repair shop and they start "talking up" the dangers of issues I didn't come in for, they will be looking at the backside of my car driving off into the sunset before they have time to put a period at the end of their sentence.

Michelle Groh-Gordy is the owner of InterActive! Traffic School Online at www.trafficinteractive.com, and writes a syndicated weekly column on driving for the publications of the Los Angeles Newspaper Group.