When something goes wrong with your car, you take it to a mechanic to have the problem fixed. Whether he works at a local repair garage or dealership, you trust that hell have the experience and skill needed to resolve the issue. Sometimes, mistakes are made. Parts are installed poorly, wrong fluids are used, and small items are completely missed. This can be due to the growing complexity of automobiles, workload, or simple negligence. In this article, Ill describe three common mistakes that are made by professional mechanics. Its worth underscoring that repair garages are usually happy to rectify their blunders as long as you let them know in a timely fashion. Changing Your Oil Filter Im going to give auto shops the benefit of the doubt and assume theyre merely forgetting to replace the filter when you have the oil changed. That said, you should have a healthy dose of cynicism with regard to the quick change shops. They might advertise an oil change for $9.99, but theyre unlikely to swap out the filter. Remember, the filter keep contaminants out of the oil. That has a direct impact on the long-term performance of your engine. When you have your oil changed, make sure the technician is also replacing the filter. Thinning Out Your Rotors Too Much When you press the brake pedal, the brake pads squeeze against the rotors to apply braking power. As the result of constant use, the pads will wear down. Eventually, youll need to have them replaced. The rotors also sustain damage over time. They can warp from the heat and friction caused by the pads. They can also develop imperfections if the pads grind against them. A mechanic can turn out (or thin) the rotors to remove the warping and imperfections. The problem is, they can be thinned too far. That poses a safety issue; the rotors can crack, leading to braking problems. If you feel a vibration when you stop your car, visit the mechanic who replaced your pads and have new rotors installed. Using Remanufactured Components The auto technicians at the dealership will typically use OEM parts to replace failing components. Your local repair garage will give you the option between OEM and remanufactured parts. The latter are less expensive, but theyre also less reliable. Defects are common and can leave you stranded by the side of the road. Unfortunately, even if you choose OEM replacements, a technician may accidentally install remanufactured equipment. It happens. Unfortunately, unless youre experienced with the parts under your vehicles hood, youre unlikely to notice. Keep your receipts and make sure the type of component youre having installed is clearly listed. If a part fails and it turns out to be a reman, youll have recourse. Mechanics make honest mistakes. But, given the opportunity, theyre usually more than happy to remedy their blunders.