I took my GMC in after it rolled to 300,000 miles during a trip and started a knocking sound. I have heard that same sound before, on other vehicles, and thought I was about to punch a rod through the block. Turns out it was not something so severe. I was provided with a loaner car, at no extra cost and they were willing to work with me as much as is reasonable and safe to stay within the budget I had.
Now, I have had this truck serviced for years by a dealer in another state, where issues were not fixed, warranty services became an issue, etc... I have been told all kinds of craziness, like my "Rotors need to be flipped", because I am a woman, and for some reason most repair shops think that means I know absolutely nothing about vehicles. That was not the case at Mazur's. Their staff listened to me, they asked questions to clarify, and took my concerns seriously. The entire staff at Mazur's were kind, and gave me clear explanations. They went over every minor and major issue with my GMC, (It has several with such high mileage) and discussed what issues must be repaired : (failing ball joints) and which ones I could reasonably wait on: (my windshield washer fluid sensor has failed = no big deal).
My GMC is now at 330,000 and is still running. I know that soon enough it will need a new engine. I have quoted that repair from many shops, including dealers and have a price range of $4000 to $6000 from all of them, including Mazur's. When that does happen I will take my vehicle to Mazur's Total Automotive. They are the only repair shop I trust to tell me the truth about what my GMC needs.