V9.

I running mobil 1 0w40 synthetic in both my e320s and was wondering how often you guys change it out. I was thinking about every 3750 miles.

I'm using castrol 5w50 full synthetic in my 911 now

ptoro01

I used to change regular oil every 3k and am running up on my second mobil 1 oil change. Starting from the first time I put it in, I did 1500 miles, changed the filter and did an oil and filter change another 1500 after. Now its at every 5k. My engine has a 150k on it so I figured I wouldnt run the oil as long as I can and I always do oil changes early anyways.

NorCal124

You can run synthetic oil 5 to 6k depending on your driving. I'm going to give the Mobil1 15w-50 extended performance oil a try.

Educaid

I've used Mobil 1 15w50 in my 300E and it is better than Delvac 15w40. It thins out and is not thick at all like the Delvac when changing the oil. I'd use it instead of the 0w-40.

V9.

Why 15w50 vs. 0w40?

NorCal124

There's nothing wrong with what you're using. I'm simply moving to 15w-50 because I do plenty of commuting and its stupid hot where I live. I want to help protect the engine by better lubricating it.

V9.

I see....but doesn't 0w40 give better initial "cold" startup protection? And how much different is a 40 and a 50 in terms of hot temp specs? I understand what you're saying though because I use castrol 5-50 in my air cooled 911 which reduces wear on startups and gives extreme heat protection.

nkpnkp

If you are using synthetic I dont see reason to change too often. I think about every 5K. In my case I drive less than 5K per year So i just do mine once a year.

crr1612

can w124s from 89 use synthetic? i though i heard that synthetic would make the engines leak oil........somethin like that

ptoro01

i changed over 6k ago and the only issue I have had with it is that the front seal which was already leaking still does. Nowhere else does it leak and I had this question as well and research showed that its a myth. So now all I have to do is change the front seal and im happy

crr1612

damn, i just had an oil change last week. if i had known synthetic wasnt bad for the engines, i woulda put it in there

NorCal124

The oil leak story is just an excuse old school mechanics made up because they're afraid of new technology and change, Lol. In some cases that's true, it also depends how bad your seals and gaskets are in the first place. But as far as useing 15W-50, if you look in the oil spec section of the owners manual 15w-50 is considered the "all around" viscosity.

kwb210

With an efficient fuel injected engine there is very little fuel washdown on startup resulting in minor if any oil contamnination. Synthetic is made to last longer and 5,000 would be a minimum interval. I always use a high quality oil filter and Mobil 1. I usually change oil based on my driving. My 2000 Toyota Land Cruiser is only driven on highway trips so I usually go to 7,500 as long as the oil color remains golden. On the 300CE I usually change it about 5,000 because it is a mix of city/highway, probably 75% city. Again, I watch the color of the oil. Frequent oil changes are certainly good for an engine, but to frequent is a waste of oil. At 80,000 miles when I remove the oil filler cap and look at the valve train it is still a silver color, no varnish or brownish discoloration, a good sign of regular oil changes based on driving.
kurt
1993 300CE Sportline

kwb210

I forgot to add I use a 0W-30 weight oil. Visit the www.mobil1.com site.
kurt

lkchris

Factory schedule for 0W-40 in our 2006 E320CDI is every 13K miles, including the breakin oil.

Of course everyone knows diesels get their oil dirtier.

Anything less is just a waste of money and polluting the environment.

It's the 21st century, guys, and the 3K oil change is very 1950s.

mgw_300e

I agree, even my old civic said right in the manual every 5000 miles, and that was conventional oil!

3000/3months is qwik-e-lube propaganda