I've been reading this tread for a few days now and as a retired tribologist, I admit having had a few laughters reading some of the posts.
''from christmas to easter i ran a valvoline 30 wt racing grade, for the rest of the year a valvoline 40 wt racing grade.''
Racing type engine is not suitable for normal road use. A racing oil is designed to be replaced after only a few hundred mile of racing and does bot contain the additive package necessary for normal street application. It has no or very little anti-acid additive, lots of anti-foaming additive and again very little ant-oxidation additive. Luckily, the engine survived, only proving the Mercedes engines are built Strong and certainly not because of the racing type oil.
After a change to synthetic oil, this comment: ''Remarkable difference. Engine is much smoother''. this is pure imagination. Synthetic had no built-in smoothness. Dyno or synthetic has nothing to do with engine smoothness.
''the chain tensioner probably got pumped up or cleaned out and the engine timing being improved.''
A timing problem has never been built into the capabilities of any oil. Again, pure imagination.
My best advise: Stick to the latest engine manufacturer's recommendations. Don't try to reinvent the wheel. The engine manufacturer, parts builders and oil companies have spent considerable amount of money, time and efforts to come up with their recommendations. Not too many people here (I included) have the knowledge and capacity to second guess them.
JackD

JackD,
Good advice except that engine manufacturer's have now got their priorities screwed up by an act called the Moss/Magnuson Act (CAFE averages) which is causing car manufacturer's to recommend oil viscosities based on helping them with their Corporate Average Fuel Economy numbers rather than long term reliability.

Nobody in their right mind would recommend 5W-20 viscosities for new ultra low emission engines. However, both Ford and Honda are doing it.

It appears that the Germans are still putting reliability ahead of CAFE averages.

I run Mobil 1, 0-20wt in my C43 and it run very smooth and allows the engine to be much more responsive.

Lighter viscosity oils allow more oil to be pushed through the crank and rod bearing providing for more heat debries removal.

It very good oil and I have no hesitation running it in my C43 or other engines.

Jeff

JackD

Sorry guy .... the engine is much smoother. Multiple witnesses and comments to the fact.

Granted it may have nothing to do directly with the qualities of a synthetic and instead have a lot to do with a worn-out chain tensioner being pumped up with the thicker oil, since the old 190 does have a chain rattle when first starting up.

I would say your comments more than likely apply to a normal engine (one not with the miles the 190e has).

Next project is of course to replace the timing chain, rails and tensioner. In the short-term it was a nice by-product of a simple oil change.

BTW, what type and weight of oil do you run in your car?

Haasman

__________________
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)

0W-20 Mobil 1 is being marketed to Ford and Honda owners. It isn't recommended by Mercedes Benz.

I'm getting the feeling that the American public has been brain washed into believing that front wheel drive, V6 engines and low viscosity oils are good. Well, there are reasons why the automobile companies are pushing those things and it is all about government regulations and controlling costs.

I'll bet that no Honda engineer would ever use such a viscosity. It makes absolutely no sense at all other than to give companies the opportunity to claim a few tenths better EPA mileage to keep them from having to pay gas guzzler tax.

well, jack d, you should stop your laughter now.

the reason i identified the manufacturer of the lubricant that i used is because valvoline used to identify some of their motor oils as "racing". they did this for single weights and for at least a 20W-50. they were available over the counter and i am pretty certain that since they carried an sae ident that they carried all of the additive package ingredients that their non-"racing" marked, over the counter lube oils contained.

it was probably a marketing gimmick, but the service manager at my old benz dealership used them because he insisted that the "racing" stipulation identified a more thermally stable lubricant.

and by the way, i have a much lower opinion of lube oil blenders than you do having worked with them all concerning their reported formulations of lube oils for stationary, spark-ignited, natural gas-fueled engines over the last thirty years.

JackD

As a passenger in the car after its change to synthetic oil,
I also felt a distinct change.
I called it a "smoother" ride.

- Haasman's Daughter

Bud said: I'll bet that no Honda engineer would ever use such a viscosity. It makes absolutely no sense at all other than to give companies the opportunity to claim a few tenths better EPA mileage to keep them from having to pay gas guzzler tax.

I would disagree completely. I am confident that Honda, Mercedes, Ford engineers all are very happy to be a part of a decade of engine development that sees better bearings, pistons, rings, cylinder bores, manufacturing techniques, etc. that allows them to use oils that have tremendous film strengths and result in lower internal friction and better performance from the engines they design.

I can not think of one race team that I was ever involved with that ran any oil thicker than 0-30wt or 5-30wt. And in many cases for qualifing oils of viscosity as low as 5 and 10wt.

High viscosity oils (40wt and 50wt), given todays better oils and engine parts are a thing of the past or an indication of poor engineering skills.

Jeff

Base oils have not changed but the formulation and synthetics have changed the oil world. All oils are good but the protection the synthetics offer is superior to regular blended motor oil. When we consider which weight of motor oil to use, some of the important specifications are the pour point, the flash point and viscosity Index. When we compare a synthetic to conventional motor oil weight the numbers tell the story. Just picking a popular brand like Valvoline conventional oil and their synthetic oil, in the 20w-50 and 10w-30 oils
Concerning the numbers: 1. Pour point-the lower the better 2. Flash point-the higher the better 3. Viscosity index-important number-oil consistency to flow, again the higher numbers better, indicates a low change at temperature.

-------------------- Pour pt. Flash pt. Viscosity Index
20w-50
Conventional All Climate -10F____430F___125
Valvoline Synthetic ___ -40F____ 465F__ 146

10w-30
Conventional All Climate -26F___410F____130
Valvoline Synthetic ____-40F___450F____140

And Mobil a popular oil with MB owners
20w-50.
Conventional. ________-17F___392F___124
Synthetic 15w-50 ____-45F___ 446F___153

10w-30
Conventional _________-33F___392F___134
Synthetic ____________-45F___471F__ 147
Synthetic 0w-40 ______-54F__ 471F___187

As I mention, for me synthetic oil’s is the best lubrication for your engine, and by reviewing the numbers you can use any synthetic weight in your car all year. But if I lived in a extreme cold climate area my old ways would say use a 10 or 5w- 30 oil, or most likely use one of the new weight oils 0w-40, 5w-40 or 5w-50. It seems in my readings that Oil Company’s in the last couple of years are producing improved engine oils. What weight, I’ve always used Mobil 1 15w-50, but I'm considering the switch to 0W-40, better start-up protection, better protection at high temperatures-and yes better mpg, and that high viscosity number of 187 for overall lubrication.
Enjoy your drive, timreid

__________________
timreid
1992 400E
euro lights
500E sway bars
210 16in wheels

Anybody know where you can get 0W-40 Mobil 1 outside of a dealer?

The Mobil 1 site says Autozone has it but I haven't called them. In any case, I suspect it'll cost more than the $4.77 for 15W-50 at the discount stores (or about $3.80 in the 5 quart containers at Walmart).

Just bought 15w-50 Mobil 1 at Kragen/Shucks/Checker etc for $3.99 a quart.

Haasman

__________________
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)

timreid,

Start-up protection is the key, after warm up, engine temperature remains roughly the same, regardless of ambient temperature.

0W40 synthetic, a very good choice.

One must not forget that their are advantages and disadvantages between conventional and synthetic. Seals etc. do not like synthetic too well.

Around 5000 miles is a good time to change the oil, whether conventional or synthetic. Contamination is more of a concern than oil break down.

Disregarding price, I would choose 0W40 synthetic as well.

__________________
Zafar
94 E320 58000 Miles

Wal Marts are starting to stock 0w-20 and 0w-40 in addition to 0w-30, 5w-30, 10w-30, & 15w-50. The price for the 0w-x oil's is near $5/qt where I live.

Synthetic oils generally have a mild ablility to SWELL seals and I disagree with the notion that 5000 mile oil changes are good for both synthetic and conventional. Synthetic oils will hold up better over time.

__________________
Brian Toscano

According to the former MB Club Tech Editor, synthetics have no adverse effects on seals in modern Mercedes.

Glad to hear about Walmarts carrying 0W-40. None of the nW-20 or nW-30 Mobil 1 oils are approved by MB. In fact, they've told their dealers not to use them.

I'll have to weigh in with JackD and Jeff. I work with a respected consultant who's an expert on oil/tribology. He's an STLE member and conducts 4-ball and wear tests on different oils and additives. He not only lets me know what's what, but he shows me data to back up his thoughts.

Automotive engines don't need heavy weight oils. Even 30W isn't necessary to prevent engine wear. The only reason lower weight oils aren't commonly used is that oil loss due to evaporation at operating temperatures becomes a factor. It's hard to make these low weight oils. These new lower weight oils such as 5W20 can ONLY be formulated using synthetic stock to preclude oil evaporation. They're not bad oils - just expensive.

Like I've said before, there's too many opinions about oil. It's like listening to Frasier and Niles Crane discuss the nuances of motor oil! Just change the engine oil and filter every 3000 miles or so with commercially available SJ oil and your engine will live a long and happy life.

__________________
95 E320 Cabriolet, 159K