victorshe95

does it matter if i put mobil 1 5w30 during my last engine oil change?

abqhudson

NO.

Yidney

Probably not, but why do it?

mis3

The local dealerships here (Toronto) used to change oil with Mobile One 0w40 but I found out they have switched over to 5w40 for a while. Don't know why.

I now go to an indie for oil change and I usually buy the 0w40 from the same dealership. Somehow MB dealerships here sell 0w40 cheaper than the stores.

To the OP, I am sure it's OK to use 5w30 occasionally but as Yidney said, why do so. If someone used it at your last oil change, don't worry about it. Switch it back later at your next oil change.

Rudeney

The weight doesn't matter. What matters is that the oil MUST meet MB spec 229.5. 0w40 is probably the best as it's a wide range of viscosity for most all possible operating temps.

mercedes4ever

Use that spec during winter, colder temps.

Rudeney

The 229.5 spec is seasonally independent. It is the manufacturer spec for the quality of oil required for the engine. The weight of the oil, as long as it meets 229.5 spec, is important based on the "season" or environmental and operating temperatures. The thing is, 0w40 gives a wider viscosity range than 5w30. 0w40 will act liker thinner oil in lower temps (0 weight) and thicker oil in warmer temps (40w). So why not go with a wider range oil? The only reason I see to use 5w30 over 0w40 is if it were much less expensive AND you live in a climate where you don't need the wider viscosity range. The reality is, there isn't much price difference in any of the 229.5 spec oils and few of us have the luxury of living in a climate that doesn't sometime go below freezing and sometimes gets very hot. Mobil 1 0w40 "European Formula" is the manufacturer's recommended oil. You can buy 5 quart jugs at Wal Mart for $26. You'll need two plus a $15 Mann synthetic fleece filter every year (or 13K miles). It's not rocket surgery!

gpdavis2

When we purchased the wife's '08 C350 Sport w/33K miles we changed to Mobil 1. About 5K miles later we had to replace the cam-seal cups&o-rings at the rear of the heads (~$900). Have always wondered if the change to the ultra-slippery Mobil 1 was the reason. Just picked up a 2009 CLK350 coupe with 59K miles and am wondering if I should stay with the more frequent oil changes and dealer standard oil. While I like the 10K and easy to remember oil changes with Mobil 1, its not worth the ~$1K reseal of the engine to me to change to same. What do you think?

Rudeney

When you say you :"changed" to Mobil 1, what do you think was in it before? The engines come from the factory filled with Mobil 1. Leaking cam plugs and the oil centrifuge seal on the rear of the heads is very common on these engines. I am not sure why it was $900 to fix that as the parts are under $50 and it takes maybe 30 minutes to replace them.

gpdavis2

Don't know what oil was in it before we purchased, but was always dealer serviced. However, I more or less 'watched' as they did the work. If you can do it in 30 minutes you are truly a wizard. Takes that much time to remove the plastic covers and crap to access the rear of the engine and another 30min, or so, to replace them. Add in at least an hour of work at the highly inflated flat-rate and it all costs too much. If memory serves, the parts (five caps, o-rings & small bolts) were $322 and the rest was flat-rate labor and the misc crap one pays for at the dealer for service. In all, I was there for ~3 hour at $165/hr (think that is the dealer shop rate), so ~$495 plus parts is ~$900+. Been absolutely dry since for the last 45K miles & 5yr, so not a 'bad' investment, just one that I don't want to repeat if Mobil 1 was the cause. Guess I'll do the Mobil 1 in the CLK and find out. Now that I know the fix I'll purchase the parts and let my local guy do the work.

Rudeney

If it was always dealer serviced, then it always had Mobil 1.

My advice - find a good indy shop and save yourself some money on future repairs!