You will see on the dipstick that it no longer says "add" and "full". Instead, it says "min" and "max". That's because most engines use some oil between oil changes and too many people complained when the level dropped below the "full" line. There can be almost a quart difference between the two lines.
Also keep in mind they may have not put in the full six quarts. At the dealership I worked at we never watched the amount that closely. We just kept adding as necessary to get close to the "max" line.
Some engines call for 4.5 or 5.5 quarts, and some shops do not bill anything other than full quarts. They might bill out six quarts which is what they open up, but they know it's important to not overfill it. Doing so can cause the oil to aerate from being whipped up by the spinning crankshaft. Air in the oil is worse than low oil level. Some engines call for odd amounts like 5.2 quarts. It's that unused half a quart from a previous job that they typically use so they don't have to bill out another full quart.
It is also customary for most shops to have a set price for the oil change to include "up to" a certain number of quarts. They often have to list the the oil and labor separately to keep track of their inventory. If the charge for the oil is higher, the remainder for labor will be less.
Please consider a to help us answer more questions.
Monday, June 10th, 2013 AT 11:53 PM