They might suggest using a fancy "Evac" system to drain your old oil, claiming it’s as effective as the traditional gravity method. However, my experience suggests otherwise. I went too long between oil changes and was informed there was sludge in the oil reservoir. After some research, I discovered that the Evac system isn't as effective at removing sludge as the gravity method. When I mentioned this to the manager, they agreed to redo it the traditional way. Indeed, the oil pan had visible sludge that the suction system hadn't removed. I recommend opting for the old-school gravity method whenever possible.