Hasn't anything to do with an oil change, but I had a dealer do a dirty to me. I took my vehicle to our local dealer (no longer in business) for regular maintenance which included oil and filter change and scheduled tire rotation. This was a necessary warranty thing. Why I thought of it I don't know, but what I did was take a whiteout pen and put a dot on the front tires only. I knew they should have been on the rear after the work was done. Upon completion of the work I looked for the dots and they were still right where I put them. You should have seen the look on the service managers face when I told him what just happened. That was the last time that dealer ever saw me. Long story short, try to do something like this to ……..ugh...… keep them honest.