How to start a fire...
 

...ask someone from Chicago what is the best pizza (or the better MLB team)
...ask someone from Boston the fastest way to get from the Back Bay to Inman Square
...or, ask a MB message board how often to change oil. I have been using Mobil1 15W50 at 4,000 miles for a 500e (86k), a 230sl(136k), an E320 (126k) and soon a C240. The dealer still says to change every 10k for the newer cars, but I can't bear it. I would really appreciate a learned opinion here,

THanks,
g

The two newer cars should be using something a little thinner but mobil 1 is good anyways. MB reccommends 0w-40 Mobil 1 for anything 98 and up (excluding pre 2005 diesels). We always suggested to customers to bring the cars in after 5k for an oil change, then the service done at the usualy 10k intervals.

The main reason manufacturers can stretch the service schedules out so far is because of the use of synthetic oils.

Ultimately it comes down to how thick your wallet is, if it's not bothering you financially, then stick to your 4,000 miles.

But really, if your using Mobil 1 you can safely extend the service to 10,000k

ozzy

oil change intervals
 

Thanks for advice, and on that note:

It used to be recommended that oil gets changed every 3-5k miles or every 6 or 12 months, whichever comes first. Does the time limit still apply to synthetic oil, or does the fact that it is inorganic mean that time is no longer a factor?

Thanks,

g

Historically, conventional oils (mineral oils which are refined from crude oil) lack the performance of synthetic oils in the areas of low-temperature performance and high-temperature oxidation stability. Conventional oils also contain much greater amounts of impurities, such as sulphur, reactive and unstable hydrocarbons, and other undesirable contaminants that cannot be completely removed by conventional refining of crude oil. It is these impurities that limit the performance capabilities of conventional oils.

At start up, mineral oils can take over 1 minute to circulate throughout the whole engine. During this period, unlubricated surfaces in the engine suffer from friction, which in the long term lead to engine wear.
Synthetic oils have an excellent ability to flow quickly through the engine at extreme low temperatures, reaching the engine in less time at startup.
Modern engines run at very high temperatures, which can cause mineral oils to break down and oxidise, blocking oil passages with sludge residue. Synthetic oils resist breakdown, protecting against engine damage, and prolonging engine life.

On a side note, I say Gino's East Pizza and Chicago Cubs...

Without getting into the pros and cons of extended drain intervals...

Strictly as a practical matter, I've found that changing oil/filter at 5K & 10K to be quite handy.

When your odometer approaches a derivative of 5000 or 10000, you know you're due for a change. (So you need not refer back to your records). It really is tremendously convenient.

Just my 2 cents... arguably worth that.

Jeff Pierce

If I had newer cars, I suppose I would use synthetic.

I have always had the habit of changing dino oil every 3k miles. Usually plenty of sales on oil, so it doesn't really cost much.

I once tried synthetic because I got some sort of special, didn't really notice any difference... so I just went back to dino