My VW Passat had a skid plate. Twice they (NOT a Valvoline shop) failed to properly secured it. (Charged me extra because it had a skid plate!) Two skid plates lost. They replaced them after a couple of months waiting for the parts each time. My daughter while driving without the skid plate managed to crack the sump. Nice puddle of oil on the driveway, but fortunately I spotted it before she drove it again. Had to pay for a new plate plus parts at the local indy - $$$.
Finally, after having the oil changed regularly at the same shop for almost ten years
, they told me they could no longer change my oil/filter as the oil they carry is NOT to VW spec. Yes, after almost ten years. Took that as a clear sign from above. From then onwards I have always done my own oil changes, including new still under warranty vehicles.
Never looked back. Well worth the couple of hours of work for peace of mind to know it's done right. Right quality full-syn. oil, right oil filter, and drained from the oil drain plug! Incidentally current vehicles don't even have a dip stick. Do they now drain from the fill hole?