Not an urban myth IMO, I have ordered alternator braces for my 2.8L V6 when the braces broke and the Isuzu parts guy gave me the Isuzu parts number and told me to drop the first and last digits. I did so and ordered the parts faster and cheaper thru the local Chevy dealer. AFAIK, this would only apply to engine parts on the GM 2.8L. This also worked on a replacement Power Steering resevoir and oil filler cap... <img src="/forums/images/graemlins/kewl.gif" alt="" />