I have been driving Mercedes diesels for longer than you have been on this earth.

^^^ Tango's an old fart. He's retired USN.




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1983 123.133 California
- GreaseCar Veg System

The legal action was actually more about oil change intervals than it was about oil type. The use of conventional oil, per se, was not the real issue. The issue was the application of synthetic oil change intervals (per an onboard oil monitoring scheme) in cases where conventional oil had been used.

This was my understanding as well. BMW had the same issue.

Frankly, I think OCI's beyond 10K miles is asking for broken down oil, additive package used up, changes in viscosity up or down, and accellerated wear. Even with a synthetic. Much as I like them I still change at 5500-7500 or once a year on all my cars. If a guy would submit a sample to Blackstone labs at 7K then he would have an idea of what's going on with his oil and set the OCI accordingly. That's about $25 or roughly half the cost of an oil change. For me it's just easier to do the latter.

If I plan in advance or for special applications I order from amsoil. If I don't plan and a standard weight oil will work I'll run down to wallyfart for mobil1. For breakin I'll use Rotella or Delo 400, both are very good dino oils. Delo is a good oil for the MBZ diesels but a 3-4K OIC seems prudent. At least IMO.

__________________
Chris Brown
"OC", So-Cal
1979 240D, 122K, 4spd, Colorado Biege w/Tobacco, Pwr Roof, AC, Cruise, Becker Corona - SOLD
Past Benzos: 71 250 • 83 240D • 84 190E • 04 C240 • 11 GLK350 • 13 c250 Coupe
http://www.peachparts.com/shopforum/...ine=1276896801

I am in the controversial camp that changing synthetic oil often leads to more wear. This is where a Used Oil Analysis can actually save you money and lead to increased life expectancy of your motor.
You realize the synthetic oil change intervals in Europe for your 2011 GLK is 15,500 miles. There is a reason behind that. Wear rates from Used Oil Analysis (UOA) have been proven to show synthetic oil is indeed higher at 3,000 miles, then 5,000 miles, much lower at 10,000 miles and at 15,000.

I read the underlying cause is the new oil’s detergent cleansing cycle of removing and attacking the protective antiwear layers formed by the previous oil additives. This is where wear rates are very high with FE count at 10ppm/1000 miles and is an acceptable loss by the car manufacturer in the grand scheme and continues until about 1000 miles when the heavy detergent cycle is used up and the new additives start forming their protected layers for long term protection that can last way over 10,000 miles where FE count is around 2.9ppm/1000 miles.

If you change it at 5,500 miles over the course of 100,000 miles you will have about 18 detergent cycles of increased wear as opposed to the US factory 10,000 OCI which would be 10 detergent cycles. In the European schedule it will only have 6 detergent cycles. Oil is basically changed because of two issues, depleted additive package and contamination, it’s been shown in newer cars, it can go a long mileage in UOA.

US schedules are based on dealerships whining about loosing their cash cow oil changes and taking advantage of the service industry's hype of changing oil at 3,000 miles. Because of that, many dealerships or service outlets would recommend a shorter oil change interval, earlier then the US factory recommend 10,000 miles just to get people's money.
Folks here the US have been brain washed by advertising for years that changing oil at 3,000 miles is good for engine. Little do unsuspecting folks know they are doing more harm to their cars then good. Yet people have gone further past 20,000 miles with much lower wear rates then at 5,000 miles.

__________________
1983 123.133 California
- GreaseCar Veg System

Hmmm...makes sense actually. I guess a lab test makes sense then, or just wait the 10K to change in order to conform to warranty requirements.

Donaldson Filter developed a nano-filtering technology that actually removes particulates making new oil out of the bottle cleaner - lab test verified! They are also of extra high capacity designed for extended drain intervals. They chose to market them thru Amsoil as their 'EA' filter line. I guess they figured the dealers were in a better position to educate the users the advantages because they are not cheap filters. I'm also guessing they do work great for extended OIC's, an amsoil benefit.

__________________
Chris Brown
"OC", So-Cal
1979 240D, 122K, 4spd, Colorado Biege w/Tobacco, Pwr Roof, AC, Cruise, Becker Corona - SOLD
Past Benzos: 71 250 • 83 240D • 84 190E • 04 C240 • 11 GLK350 • 13 c250 Coupe
http://www.peachparts.com/shopforum/...ine=1276896801

I have to wonder if what is actually being demonstrated here is not that wear rates decrease, but that the dispersant capacity of the oil is diminished as a function of time in service, creating the appearance of decreased wear rates. That would be consistent with the increase in wear materials concurrent with the introduction of fresh oil.

This makes more sense to me.

I'm not clear how a detergent property would/could 'wash away' the additive package.

My MBZ/BMW indy says 5000-5500 is long enough unless you're going to lab test.

I also don't understand why fresh oil wouldn't be better than old used oil. And what's the matter with a high detergent property? It has to work better for ring grooves, hydraulic lifters, any place where sludge and carbon build up is detrimental.

When I did the ATF change on the old bimmer it got dirty really fast, kind of a gray matter. I figured it was trans-band cleaning and putting more glop into suspension. They give those trannies 100-125K miles as 'lifetime', and hence their 'lifetime' synthetic ATF. Meh. An un-serviced trans just isn't going to last longer than one with a fresh filter and fluid. Burnt ATF just isn't going to out perform new synthetic fluid.

__________________
Chris Brown
"OC", So-Cal
1979 240D, 122K, 4spd, Colorado Biege w/Tobacco, Pwr Roof, AC, Cruise, Becker Corona - SOLD
Past Benzos: 71 250 • 83 240D • 84 190E • 04 C240 • 11 GLK350 • 13 c250 Coupe
http://www.peachparts.com/shopforum/...ine=1276896801

The big boys (railroads, etc.) do oil analysis and plan oil changes based on that. it's harder to see it as making economic sense when an oil change means buying two gallons of new oil instead of 250, though.

__________________
1981 Mercedes 300TD, 1994 Honda Civic Del Sol
http://mefi.us/images/fuelly/smallsig-us/67195.pnghttp://mefi.us/images/fuelly/smallsig-us/103885.png

That would makes sense, but at 20,000 miles the UOA test has shown FE count at 3.3ppm/1000 miles showing an increase. This means the oil has not had a diminished capacity. Wear rates can go up to 5-7ppm/1000 when a change out is needed.




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__________________
1983 123.133 California
- GreaseCar Veg System

FE is iron, right? Is that the only wear indicator?

Seems to me an oil analysis is customized to the type of engine it came out of, and based on it's component make up then material levels in the oil determine no wear or wear, and if there is wear then what is wearing. At least that's what I've seen on sample reports from Blackstone Labs. They can also determine the existing life of the oil sample based on the number of miles in use and presence or lack thereof of the additive package.

__________________
Chris Brown
"OC", So-Cal
1979 240D, 122K, 4spd, Colorado Biege w/Tobacco, Pwr Roof, AC, Cruise, Becker Corona - SOLD
Past Benzos: 71 250 • 83 240D • 84 190E • 04 C240 • 11 GLK350 • 13 c250 Coupe
http://www.peachparts.com/shopforum/...ine=1276896801

When an oil change occurs, the new oil has detergents that attack the remaining oil that was left after the oil change and neutralizes the remaining acids and other contaminants in the engine. The detergents do not decern what to attack, but attacks everything. They prevent the adhering of any antiware elements to the internal surfaces. Therefore the cleansers reduce the effectiveness of the additives and cleans the previous protective antiwear layers along with preventing it from being replenished. As the heavy detergents are used up in the first 1000 or so miles, the wear additives are able to rebuild the protective layer that stops the wear at those internal surfaces.
There are still detergents in the oil that prevent sludge and carbon build up, but they are not as strong as when the oil is first introduced into the engine.


FE is iron and Yes there are others. But Iron is a good indicator.

Aluminum: Pistons, bearings, cases (heads & blocks).
Chromium: Rings, a trace element in steel.
Iron: Cylinders, rotating shafts, the valve train, and any steel part sharing the oil.
Copper: Brass or bronze parts, copper bushings, bearings, oil coolers, also an additive in some gasoline engine oils.
Lead: Bearings.
Tin: Bearings, bronze parts, piston coatings

Yes oil analysis is customized for each engine. This is why you would start off with a baseline and go from there. Then you'll have an idea of how your engine is doing long term and how long your oil can last.


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__________________
1983 123.133 California
- GreaseCar Veg System

According to these guys, 43% of engine wear comes from dirt.

If we are worried about wear, then read about their advanced filtration systems.

The next largest wear item would seem to be startup. One because of oil draining off engine parts. Two from cold weather starts and poor viscosity and flow rates. Synthetics should be the winner on both of these. Viscosity and flow rate on synthetics is far superior to dino oil hands down.

A transmission has total energy losses of 40% due to the trans pumping its fluid, and the trans is 37% more efficient at running temps. So, when it is very cold, you are making it easier on the trans and the engine until it reaches opperating temperature.

A number of other suggestions were made here that I will try to get Amsoil to answer, hopefully, in writing.

Attached Files

	AMSOIL ON OIL 1.pdf (217.8 KB, 132 views)
	AMSOIL ON OIL 2.pdf (471.0 KB, 172 views)
	AMSOIL ATF Vs. FORD MERCON 5.doc (34.5 KB, 168 views)
	TSB DT-2004-11-01 How Cold Temperatures Affect Auto Trans Efficiency.pdf (42.6 KB, 101 views)

Oh I don't doubt that dirt is one of the main sources of wear. But UOA does tell you what is happening to the oil.
Remember there are two reason why oil should be changed out, depleted additive package and contamination. Dirt is part of contamination. The other, the additive package, only accounts for 3% of the total volume of oil. But it accounts for around 90% of the protection by having the additives require heat and pressure to bond with the wear surfaces, and it takes several cycles for that to happen. Other part of the protection includes the oil itself where it is doing most of the protection during the detergent cycle.

If you can minimize the contamination through better filtration, be that of Air and Oil, you can theoretically “top off” the oil with new oil to replenish additives. A UOA will tell you if your “Total Base Number” (TBN) for additives is at an acceptable range.
In your Amsoil advertising publication, they tout the 25,000 mile/once a year oil changes with their oils that will bring better wear protection, fuel economy, less oil consumption and money saved. This being with the stock oil filter. Of course I wouldn't want to push the stock oil filter past the manufactures suggested oil change without a UOA. The UOA would tell if the insolubles are too high that warrants a filter change.



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__________________
1983 123.133 California
- GreaseCar Veg System

It's interesting to read what one of the major oil analysis labs thinks about synthetic oil:

http://www.blackstone-labs.com/faq.php