Wear

Well, there are many fine oils working without esters, too.

The right mixture between e.g. primary / secondary ZnDTP's (immediate protection @ cold start, protection over time) and choice of extreme pressure additive is very important. To use one additive in too high concentrations may spoil the oil. You may get chemical corrosion with high ZnDTP levels. This is the reason why I am against the usage of "wonder top-up additives"

The hot protection of 0W-X viscosity oils is no issue. The shear stability of the oil depends on the viscosity modifier used, and the base oil of course. The sequence VIb test by the way is the test which seperates European from US oils. This test is used for the release of ILSAC GF-3/4 oils. The Fuel economy results depends on how much the oil is sheared before it starts to get thick again. There are people joking that this test is nothing but the most expensive way to simulate a Bosch injector.

The oil viscosity infuences the wear protection, too. But I can't say how much the influence is today, it used to be big in the past, but I guess with modern additives this somehow has changed.

HTHS is the most overestimated influence these days concerning wear. I have never seen any wear which could be HTHS related in an engine.

To do many cold starts without heating up the oil is wearing any engine up. Most additives do have to have at least 60°C to start to do their protective magic.

I agree with Calissa that other good oils w/o esters are working too but I also beleive to "help" build a perfect oil I'd want ester to protect during start before other additives went to work . I also agree flow is needed o protect an engine during start up .

I also think zinc , certain esters , oil soluable moly and combo's of the above can cause copper and lead corrosion , thats why tests were developed to test for such .

I am very curious about oils but for the most part we are able to buy oils these days so good some engines don't deserve their use . There is junk , good , sonic and supersonic oils . A good oil can get beat up well in one engine/trans combo and allow for high wear and general poor service while that same oil does very well in another engine/trans series .

Finding what works in your engine and for your budget is part of the key to proper maintanence . Same can be said for some gear oils .

I too am against wonder additives . I've not seen any of them work wonders . Wonderfully thinner wallets yes , wonderfully longer engine service life no .

If one deems an oil needs doped because it's lacking in something, buy a better oil for the engine is my opinion .

The Valvoline Synpower additive at 1 ounce per quart does lower iron signifigantly with some low cost oils though and bumps the TBN up . It's the only engine oil additive I would personally use or advise use of to my friends . Mostly because it does not drive up operational costs too much .

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"There are people joking that this test is nothing but the most expensive way to simulate a Bosch injector."

Agree it's funny but whats funnier is the GM test engine still being used . I beleive there are other engines made that are much tougher on oils that could be used for the sequence testing . Thats a dinosaur of an engine .

I like the way the ACEA goes about it myself .

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I also think zinc , certain esters , oil soluable moly and combo's of the above can cause copper and lead corrosion , thats why tests were developed to test for such .

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Wrong believe. High TAN numbers / acids in the oil cause copper lead corrosion. These tests are developed for the sake of "backwards compatibility" for older engines which are still on the market.

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Agree it's funny but whats funnier is the GM test engine still being used

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The sequence VIb engine is a Ford engine to the best of my knowledge.

Nope . Oil additive suppliers are aware of copper corrosion problems when for example certain oil soluable moly is used with certain base oils . R.T vanderbilt speaks of potential problems at their site .

Here at Noria is an article tracing zinc and oil cooler corrosion . Other white metals can corrode if the formula is not correct thus bench tests are out there to test for such

Corrosion Tests TEST ASTM** TYPICAL PROPERTIES
Cu Corrosion, 3 hrs @ 121C/250F
Zn Corrosion, 3 hrs @ 121C/250F
Pb Corrosion, 3 hrs @ 121C/250F
Al Corrosion, 3 hrs @ 121C/250F
50/50 Pb/Sn Corrosion, 3 hrs @ 121C
1A - no tarnish

I will try to find a file I have that spells out the max allowed copper corrosion for API diesel engine oils and post here .

Read about max allowed lead corrosion in diesel oils here . I'll come back with another showing max allowed copper .

http://www.infineum.com/information/heavyduty2002.pdf

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Read about max allowed lead corrosion in diesel oils here . I'll come back with another showing max allowed copper .

Good point. But this is a heavy duty Diesel Spec which you are referring. When I was talking about backwards compatibility foe older engines, I meant older Gasoline engines.

I cannot prove this to you, but I am convinced that chemically seen there is a different mechanism behind copper corrosion in Gasoline and Diesel engines.