My Ford Focus was overheating and Preferred found the cause to be a bad radiator with low flow. We had put this radiator in from pick'n pull after my son damaged the original driving into a ditch. We took it to Preferred about a months ago when it was overheating on longer trips and they didn't diagnose the problem then but only charged $57 for diagnostic. Shortly afterwards a rubber plug blew off while I stopped at the bank and when I came out coolant was all over the parking lot and I found a rubber plug under my car. I reinstalled it with new clamp and thought that maybe coolant had been leaking past a loose clamp. However the overheating problem continued even though it had plenty of coolant. We took it in again and this time they finally diagnosed the problem as a clogged radiator. I asked it they could include the 57 previous payment as part of the payment for the new 800 charge to replace the radiator but they wouldn't do it. If they had that would have given them a 5 star rating.