Getting the wrong part isn't part of the intended service that they provide. Many times a manufacturer will make a running change on an automobile and that change might not be reflected in the parts book at first glance. Many times, the part will indicate X will fit up to a certain serial number and then Y needs to be used for the rest of the model year run. When I ordered the exhaust for my Benz, I got the wrong one and when I called the aftermarket manufacturer and worked with them by e mail with pictures, they figured out what was needed. The corrected the next issue of the parts book. When I go to the dealer to order any parts, they will not even talk to you if you don't have the vehicle identification number. This is the only way that their parts system will look up a part... it is that vehicle specific. When I try to order parts for my 1978 Superior Cadillac Ambulance, they look at me like I have 3 heads. Most counter parts people don't have a clue as to what a Cadillac Commercial Chassis Car is. It looks like a Cadillac on the outside and the inside front compartment, but that is where all similarity ends. The drive line, suspension, brakes, etc. are all over sized and extremely heavy duty. Even the differential and wheels are unique to this vehicle. It took 4 tries before they could even get a power steering hose that would fit, and then it wasn't even a duplicate of the original. If I try to order parts from the Delco Parts division, it is the same hassle, and the Cadillac Dealership just throw their hands in the air and don't even try to order the parts requested unless I bring in my Cadillac Parts book and give them the parts numbers. In the old days, getting the correct part was easy, but with todays vehicles, it is next to impossible.
I was talking to a friend that works for a automobile dealership as a service manager. He told me that certain vehicles they have to hook them up to a computer that will send the information back to the manufacturers computer and then tell them what the problem is and the parts to repair it. All updates to the vehicles computer are also done at this time. The days of diagnosis and repair by the average mechanic (modern day term = technician) are gone. It has gotten to the point that the average person just doesn't have a clue as to how a modern automobile engine operates. Electronics and computers control everything except for putting the gasoline into the tank.
