UOA on OE Toyota oil- 998 miles.

Silicon was high, silicon is dirt of course. I doubt it's from an ineffective air filter or dirt intrusion from another source. Most likely something is sand cast and there was sand left on the casting. I would say you did not waste your money changing oil so early, others may differ

 

Very nice. I was just hoping that someone would do this. Previous early first oil changes in Prius have not shown nearly that much Si, so please make sure that your engine air filter is doing its job well. Consider another UOA, with the obvious hope that the Si will plummet. Then we can treat it as 'built' into the engine.

edit: PriusTeam, please pass this one along to your friends in Japan I doubt it's what they expect to see either.

 

Thanks for posting that, my car is at about 1400 miles and I'm going to change oil and filter tomorrow.

 

Agreed.

 

I think its probably more likely that sealants and sand cast residue are the source of the Si (as noted in the report). I found a similar high Si when I changed and had a UOA done on the ATF in the transaxle @ ~10k miles. I drove another 10k with the replacement ATF and did another UOA and the Si level dropped to less than half of the previous level.

 

Finally the answer I was looking for in my other post. Consensus in changing the oil before 5K miles. Someone has pointed out what we are really seeing in the UOA.

EDIT, Posted UOA over at BITOG
Looks like this original fill is a break-in oil.
The high silicon could be a purposeful wear in agent.

 

The high Molybedum (sp)? yes certainly maybe a break -in additive, Silicon, no way. Silicon = bad

On edit, Moly was maybe an assembly lube, probably camshaft. Any body replaced a cam before? remember the black grease you were supposed to smear on the lobes?

 

As far as Mobil 1 0W-20, I had excellent results in my 2004 Prius, using the dealership oil filter and 10,000 mile intervals. With my FJ Cruiser, the 0W-20 performed poorly (Low TBN, high nitration, high oxidation, it thickened to a 30, etc) after only 4,000 miles

 

Your molybdenum being ten time average could explain the color. Molybdenum is of course a lubricant that would have been added, it is not normally something you would find from wear.

 

True.

Without an analysis of new unused factory fill oil, most (all?) of the rest is pure speculation.

 

Here is my first UOA from Blackstone @5100mil

Very similar numbers more metallic thing indicates a little more wear.

Most surprising is the OIL Type. I wrote that I do not know the oil type and Blackstone indicates 5W20 ... factory fills that but requires 0w20 in the manual and on the cap??!!! Pretty suprising!!!

And of course I had big "misunderstanding" at the first oil change... invoice again shows 5w20 and when I "protested" they said that is just a misprint and they of course used the 0w20 (at the cheaper price yeh right!!!)

Here it is.

 

Don't worry, Blackstone does not know that it was a 5W-20 or a 0W-20 oil, they are guessing. What they do know is that the oil matches the 100C viscosity for a 20 weight oil. They are also mistaken about the engine size, showing that you lost 0.3 liters of displacement (the 2010 engines are 1.8L, not 1.5L).

In order to tell a 0W oil from a 5W oil, one has to bring the oil down to -30C, -35C and -40C and measure the cold cranking viscosity as measured by the test ASTM D 5293 and measure the cold pumping viscosity as measured by the test ASTM D 4684. Here are the differences:

0W Cold Cranking: 6,200cP @ -35C Cold Pumping: 60,000cP @ -40C

5W Cold Cranking: 6,600cP @ -30C Cold Pumpling: 60,000cP @ -35C

There is no way Blackstone did these tests on your oil without you paying them to do so, assuming that they have the proper test setups and cold box to do them in.

 

Thanks for the information on the cold cranking ... looks like the 20 part is the real important anyway... where I live -10C is a rarity anything colder than that happens once in every 10 years .... (my car is in a garage all the time although not a heated one).

As far as the engine thing goes. I think I did not write it on the slip and they just guessed it (perhaps few 2010 Prius owner sent in samples...) I make sure next time I correct it ...

I surmise that it makes no difference in their analysis whether the engine 1.5 or 1.8 L

 

Here is my UOA @40k

The only worries is that now Blackstone indicated 5W30 ... dam I hope Toyota puts the right kind in the car (but I had no real mpg hit as a matter of fact it was better the earlier period)

 

LOL.

One page of answers on Si and ALL of them wrong.

High Si levels in break-in oils is from silicone sealants:

Silicon Doesn't Always Mean Dirt



If this was indeed dirt (silica) it would be combined with high wear elements (Fe, Al, Cr, Pb).