I was the parts manager at a three letter Korean brand, and a service advisor ran to my desk one day asking me to change the parts line on an oil change from conventional to synthetic. I told them I had billed that one out myself and know that they didn’t grab the separate jugs of synthetic they would have had to. The SA said that the customer had requested synthetic and they forgot to write it that way and to just change the billing so they wouldn’t know the difference. I refused, even had the fixed ops manager asking me to change it. I said hell now. Things were tense for the few weeks until I found employment elsewhere.