that's a nice deal, maybe they're starting to switch to 0w20 and giving away the extra 5w20 supplies they have. The recommended oil is 0w20 but honestly I didn't see any major improvements when I did the switch from 5w20.

I have bad experience with guys changing oil in my cars/truck, left the filler cap open, putting in the cheapest oil and filter and worst of all putting in 10w30 when the recommended is 5w30. Shops don't make a lot of profit from discounted oil changes, somehow they have to recoup it (they're going to ask you for new blades, filters and recommended services)

 

also, pimpled kids that physically do this, use power tools on drain plugs. you know how much it costs to replace oil pan?