If they flush it, it should be with a heated machine and work like a Wynn's machine does.
I'd question them hardcore on how it works and demand to see the machine. Otherwise, you'll take your business elsewhere.
2000 F-350 Lariat Super Duty, Dually, CCLB, 7.3L
330,000 + miles
+1 with the above. My dealer uses the machine for flushing so I have them do it. I have tried to have the dealer do the flush every other interval. I will drain and refill the pan myself on the interval.
Officially The Biggest Midget In The Game (In support of Zmann's request)