there is partial truth to that. It's up to the dealers discretion and some of the variables aren't just walk in parts sales - if they lower their parts prices by a % then the service prices for Inspections & maintenance are lower overall also. The labor rates & times are the same but they offer a "more attractive" service pkge price to the customer. Many do this this time of the year when people are planning vacations & road trips - they make it up in volume. It's called the "slow dime vs the fast buck". It also helps car sales this time of year - it's economic shuffling.