Neighbor was out today changing the oil in his new-ish C-Class Merc. He didn't have ramps so he was one wheel on the curb crawling on the ground. I glanced at his choice of oil and noticed he had Mobil Super 5w-30. I asked if I could offer some advice and told him about MB requiring the use of certain oils and I mentioned that I believe his car needed a 229.5 oil since it was the gas V6. I also mentioned that a good use of $50 was on some ramps. Since he already drained the oil my offer to use mine was for naught. It was only a block from my house so I took the dog home and eyed up my stash. Grabbing 2 jugs of Valvoline MST bought recently from WM for $10.47/jug and my funnel, I went back. He still had the receipt for the Autozone purchase of 8 qts of Mobil Super so I offered to sell him the Valvoline for $20. I showed the back of the jug with all the MB, VW, BMW, and Porsche approvals and he agreed it was the right choice. I lost a couple bucks but know there's a healthier Mercedes on the road. A couple weeks ago he told me he was doing it himself because the dealer wanted $100 for an oil change. He told me he paid $80 for the oil and M1 filter at AZ ( )so I explained that Amazon and Walmart are your better choices. I told him to get two more things to make life easier...rubber gloves and the cheap pick set from Harbor Freight to get those o-rings off the filter housing. I left feeling like a Boy Scout.