Quote Originally Posted by aaronng View Post
I thought that the flow rate out of the sump drain hole was quicker than through a measly tube that fits in the dip stick hole. The only way I can see this benefitting the mech is that he removes only part of the oil (say 3L), so that it takes less time (doesn't have to wait for every last drop to come out before putting the bolt back on), uses only 3L of his oil and saves him 20 cents on that sump plug washer.
i would back this opinion...

if you look at it from a process efficiency perspective (where volume of work is your coefficient for increasing bottom line profit) if you had a brain you would do it all whilst your under the car and stop doubling up your time working from the top and then the bottom.... only a dumb shit would do it the other way if they were thinking about time spent and profit per job...