RotellaT6, 5118mi, Subaru Legacy GT. High Chromium

[SCHM1AN]

I just received this last report from Blackstone about my Rotella T6 sample which has an alarmingly high amount of chromium. Iron is still up and so is aluminum. Is there enough reason to panic here?

Code:
M1 (1) GC AMSOIL (1) AMSOIL (2) Rotella Unit Averages Universal Averages

Calcium 2995 2003 1894 1718 1073 1937 2008

Zinc 993 945 1059 837 1096 986 956

Phosphorus 898 824 843 714 850 826 806

Magnesium 24 431 90 32 778 271 365

Boron 117 21 45 40 17 48 46

Molybdenum 79 14 4 2 46 29 72

Iron 11 22 24 38 34 26 9

Copper 15 21 11 8 13 14 9

Sodium 25 11 10 7 16 14 28

Silicon 15 12 11 5 5 10 11

Aluminum 4 7 4 9 9 7 4

Chromium 1 3 4 5 8 4 1

Potassium 1 4 3 3 1 2 2

Nickel 1 1 1 1 1 1 0

Lead 0 1 1 2 2 1 4

Tin 0 0 2 0 0 0 1

Mangenese 0 1 1 2 1 1 1

Silver 0 0 0 0 0 0 0

Titanium 0 0 0 0 0 0 0

Barium 0 0 0 0 0 0 0



SUS @210F 65.7 64.1 67.0 67.8 71.2

cST @ 100C 11.8 11.35 12.16 12.36 13.28

Flashpoint 385 365 405 430 360

Mi on Oil 5717 6598 5276 5997 5118

Mi on Unit 70208 76806 82082 88096 93215

 

[ATS-V]

Is this purely a short trip car? If so, you need a thin oil not thicker.

It looks like something is abrasive but Si is not out of line. if you have a scanner I would monitor knock as high iron and chromium are classic tell tale signs.

 

[SCHM1AN]

This car is used as a DD car, but only saw 2 autocross events last year. The Rotella sample was the mark where I began a new job which is 25mi away from home instead of the previous 5mi commute that I had. I was planning on doing a lot of autocross this summer, but after this UOA I'm starting to have second thoughts

 

[fdcg27]

Potassium is low but sodium looks a little high.
Iron looks like it's trending higher although lead remains low.
IIRC, none of the oils you've posted UOAs for use sodium as an additive.
HG?

 

[SubLGT]

the beginnings of a broken ring land ????

 

[SCHM1AN]

That's what I think; the beginning of a ringland failure. I'm going to be doing a compression test later this week to verify

 

[Clevy]

So your running these top notch oils less than 6000 mile intervals. Have you tried a conventional to compare data vs these oils.
Is 5ppm of chromium high? Did blackstone flag it or have they got any universal figures to compare against?
I wouldn't worry too much yet. Have you tried a conventional hdeo. They tend to work well in turbo applications.
Sorry I can't be of more help. Your data baffles me. You are using the best oils available yet still have potential warning signs.
I will be paying attention to this thread.

 

[SCHM1AN]

I'm thinking I actually may have a blown headgasket as I got home (very windy day) and saw some smoke in the rearview mirror. I put the car in my parking spot and revved the engine slightly and saw more white smoke coming out . That doesn't explain the wear though.

I don't have any UOA comparisons against a conventional oil, but I do track mileage religiously and saw a 20% increase in mileage when I switched from conventional to synthetic if that helps at all

 

[bluesubie]

Some others can chime in, but I believe a head gasket problem would show a bit more potassium and sodium.

What year LGT is this and does this MY have ringland problems as bad as the STI's?
Do you have mods? Here's a run on conventional Esso Protec 5W-30 from a Stage II LGT Spec B.

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2959107#Post2959107

A synth blend like T5 might be fine, but I wouldn't monkey around too much with conventional. Especially if you still have your AVCS and turbo screens. SoA still recommends synthetic at 3,750 miles intervals for pre 2011's, as you probably know. If you're really concerned do a Dyson Analysis (especiallly if wear doesn't drop on the next one). He has a lot of experience spotting problems in our cars.

-Dennis

 

[SCHM1AN]

Dennis,

I've got a 2006 LGT. The engine has not been modified at all, but I do still have the turbo screens in place.

 

[friendly_jacek]

I had high Cr (similar to yours /1000 miles) in 2000 NA Subaru that was used for short trips and ran rich like pig on cold engine (OEM, no mods).

 

[cptbarkey]

if you are already having white smoke out the tailpipe then that is a dead on sign. check the coolant overflow for bubbles as well for more confirmation.

 

[SCHM1AN]

What was the end result? Did you have a ringland failure?

In this sample the trips were typically longer. Earlier samples had short commutes

 

[friendly_jacek]

No, there was no engine problem. The car was totalled at 60k. I'm saying high Cr is expected with short trips and rich conditions.

 

[Trav]

Any idea what the fuel dilution is?
The white smoke is interesting. If its not a HG it could be an injector issue, one that sticks open or leaks for a very short time will put white/grey smoke out.
I did some on a GM that one would leak when the injector got up to temp, cold it was fine, white smoke.

Edit: Course its a Subaru and HG is an all to common failure.

 

[bluesubie]

Originally Posted By: Trav
Any idea what the fuel dilution is?

I completely missed the low flashpoint!

-Dennis

 

[SCHM1AN]

Fuel dilution was 0.8, the highest amounts I've had in a UOA yet. Everything else was 0.5 or TR (trace). Also notable is that the insolubles were 0.3, another maximum amount