koskesh

I am contemplating if I should switch to synthetic oil (mobil 1 0W-40). I have a 1997 E320 inline 6 with 120,000 miles and it uses little to no oil. Since I'm a bit OCD about my car I want to switch to synthetic for the added protection.
If not synthetic my other choice would be the mobile 1 7500 extended performance.
In either case I will be changing my oil every 4000 miles max.
Your advice is highly appreciated regarding this decision.

btw, what's a good filter to use in either case?
I think I might use the mobil 1 filter with this which I think is the same as the recommended fleece filter, if not I will be changing it every 4000 miles so it won't matter anyways.

thanks

patrick_y

I'm not an expert about the 97 E320 with the inline engine regarding what filters it can take and if it can do with synthetic oil, but if the car can use synthetic oil, I'd go with the synthetic.

The filter, I'd just go with the stock Mercedes-Benz filter, if they have a fleece filter model that fits your car's engine then I recommend that you use it only with synthetic oil (I personally believe that the fleece filter works better with synthetic).

Musikmann

There is no question that synthetic oil is better, in general, but the question that remains is: should you switch over in mid-stream? I have heard good, bad, and indifferent answers to this.

Another question that comes to mind is this: Were the synthetic oils being made when your car was new NO damn good? And so is that why MB was not using them then? I think they started putting synthetics into the USA-bound vehicles in mid-1998.

If that was my car, I'd stay with conventional oil (Mobil 1 extended sounds good to me) and change it (with filter of course) more often like you are thinking. That might satisfy your OCD tendencies

And like Patrick, I would use a stock OEM Mercedes filter. Plus, I think he is correct in that the fleece filters/synthetic oil is the correct match.

In any case, good luck!
Musikmann

koskesh

thanks for the replys, what is the oem filter used by mercedes and where can I obtain them besides the dealership? thanks.

E-Klasse

Use synthetic but don't go with the 0W stuff. Stay with the same weight as what you have been using like 10W-30. I use AMSOil 10W-30 Extended Life in my 96 E320 with the inline 6. Change it every 5000 miles.

ccmbduong

My '96 E320 I6 now has 71K. I switched to Mobil 1 10-30W since 45K or about. The reason I switched not because of Mobil 1 is a good lubricant (it is), but because I don't want to change oil (I do it myself) every 4000 miles. Now I change Mobil 1 every 10K miles, no problem so far. I know that Mobil.com recommends 0-40W Mobile 1 oil for my '96 E320, but I don't believe that it's that much difference than 10-30W or 5-30W, because at hot engine temperature its viscosity would be almost the same. How do I know? I am a Chem. Engineer.
My son's '97 Maxima has 105K miles, and I just switched his car to Syns oil (too lazy to cahnge oil every 3-4K miles), no leak that I can find after 2 months. I am told that old (70K-100K miles)American made cars should not be switched to Syns oil because of poor tightness (?) of head gasket design/clearance... My friend told me that's what happened to his US car... Go figure...
Good luck

koskesh

ccmbduong,

Nice to have someone with a science background shed some light here. so there's really not much difference going from a 30 weight oil to a 40? I know the previous owner of my car used 10W-40 in it so I might just stick to a 40 weight oil, since it's a relatively big engine and I get paranoid especially in the summer and traffic jams. If you could explain in a little more detail how they're different (or similar) so I can understand, I'm a biomedical engineer (not quite as much chem background as you) so don't be afraid to get technical here thanks

E-Klasse,

Why don't you think I should use the 0W-40 stuff? I live in Iowa and in the winter we see some very low temperatures. And besides don't you think the 0W stuff provides better lubrication when starting a cold engine? thanks for the reply.

Musikmann

I don't know off hand, but it should be a pretty easy Google or eBay search.

E-Klasse

2 reasons:

Your car was designed before 0W oils were around and the oil recommended was 10W. The seals were designed and tested with that weight. Your car has aged making it more likely to leak. a 0W oil will find a space to leak out that a 10W may not have gotton through.

Even though it is a synthetic it has additives. The wider the range in numbers the more additives or polymers. A 0W-40 has more polymers then 10W-30 because of the range from 0 to 40 is greater than 10 to 30. It is these additives and polymers that create sludge in your engine so why would you want more of them.

perzbenz

koskesh... ROFL

ima55r2

Check your manual for the proper viscosity based on ambient temperature ranges and pick the weight accordingly, but I would stick with whatever grade you are using now and start using the equivalent synthetic. Go lighter for less friction if you wish, but not heavier.

Dino oil and synthetic are fully compatible...that’s what the new mobil oils are...a blend.

Synthetic offers superior performance in all categories when compared to dino oil and it is worth it. MB mandated synthetics for the extended service intervals and allows 10k miles between my free services, but changing it out at your old schedule is up to you.

You will notice a change for the better as soon as you drive off with the new synthetic oil.

koskesh

I thought someone would eventually catch that