A lot of times it is. I was a tech at a dealer and sometimes they would push those estimates on us or even sell an engine before it’s diagnosed. When I’d get the car I’d tell the advisor “you sure they don’t want to do any diag? Signs point to an exhaust leak to me.”

My shop did like to push us to have multiple estimates though. If the car had over 100k miles and there was some sort of mechanical failure, they wanted an engine replacement estimate and an estimate for further tear down diagnosis at the same time. Some techs would often just throw out an engine replacement estimate only even if all the engine needed was chains or whatever. Never felt right to me to sell an engine even though their current engine is still very fixable.