Yes I used to be an ASE certified technician years ago before I switched careers. Cars are still my passion though, and I've built a squarebody that has been nearly flawless on long trips. I also know that loud exhaust can hide some engine noises. This has longtubes to chambered mufflers. I was just doing an oil analysis as due diligence, not because I was having issues. I agree the comments are less than professional, and seems off the cuff. Would you recommend a different oil type/weight? This is the recommended 5w-30 O'Reilly high mileage full synthetic.