05 Audi S4 Motul 300V 5w30, 5150 OCI, 67k

[dparm]

Code:
OIL 300V 5w30 300V 4T 5w40

MILES IN USE 5150 5026

MILES 67761 62611

SAMPLE TAKEN 4/7/12 5/11/11



ALUMINUM 4 10

CHROMIUM 0 0

IRON 13 7

COPPER 7 8

LEAD 2 2

TIN 0 1

MOLYBDENUM 598 157

NICKEL 0 0

MANGANESE 1 1

SILVER 0 0

TITANIUM 0 0

POTASSIUM 3 3

BORON 33 106

SILICON 13 11

SODIUM 6 2

CALCIUM 1562 2411

MAGNESIUM 913 25

PHOSPHORUS 884 871

ZINC 951 1073

BARIUM 0 0



INSOLUBLES 0.3 0.2

WATER 0 0

FLASHPOINT ºF 405 385

SUS VIS 210ºF 65.3 68.6

cSt @ 212ºF 11.69 12.59

TBN 5.1 2.2

TAN 6.8




Blackstone comments:

Thanks for the detailed note you included with this used oil sample. Just because an engine see a lot of WOT runs and is driven aggressively doesn't necessarily mean that it is abused or not in good condition. Your S4's V8 is a perfect example of that at 67,761 miles. Universal averages for Audi's 4.2L engine are based on about 5,600 miles on the oil. This oil was in use for 5,150 miles and wear compares well with averages. The viscosity read up in the 5w40 range, but that wasn't a problem. The TBN was strong at 5.1 and the TAN was acidic at 6.8.



Interesting how my wear metals all went DOWN on the 5w30 verus 5w40 despite being run for an almost identical amount of time, same number of track days/autocrosses, and the same amount of makeup oil added.

I'm glad to see the aluminum number come down after two consecutive "high" UOAs.

Also looks like the "4T" 5w40 I ran last time does indeed contain more boron and calcium than it's auto version, but less magnesium and moly. I wonder if that extra moly in the auto version is why the wear numbers looked better?

Should I be changing this sooner due to the very high TAN-TBN ratio? Blackstone flagged the viscosity as being out-of-range...so this actually thickened over the course of the OCI.



New fill is Renewable Lube Bio-SynXtra 0w30 (VOA coming shortly).

 

[A_Harman]

Since you're running an ester-based oil, the TAN should be high, but the fact that TAN is higher than TBN bothers me. Do you know what TAN starts at for 300V?

 

[dparm]

I don't. I have a bit left in the container -- maybe I should send it in for a VOA?

Starting TBN is about 11.

 

[A_Harman]

Another noteworthy item is that the auto 300V still has 5.1 TBN, and the 4T 300V was down to 2.2 at almost the same number of miles. Maybe the higher Mg content helps TBN retention?

 

[ltslimjim]

^as well as better a neutralizing than calcium alone, looks somewhat like a HDEO cal/mag ratio.

 

[A_Harman]

Originally Posted By: dparm
I don't. I have a bit left in the container -- maybe I should send it in for a VOA?

Starting TBN is about 11.


That would be a nice piece of data to have, although I'm not sure what strategy you could build around it. Maybe if you find the Virgin TAN is 4.0 (just to pick a number), you could subtract it from the Used TAN to get a "Corrected TAN". Then once the TBN decreases to the Corrected TAN, the oil is due to be changed. Motul should be able to advise you on how to manage TAN/TBN for their oil.

It sure seems wrong to condemn an oil that starts out with 11 TBN at only 5000 miles. Especially at Motul prices.

 

[Turk]

Sung to "Hello Dolly":

I said Hello Moly.
Well, Hello Moly.
It's so nice to have you back where you belong.
You're lookin' swell Moly, I can tell, Moly.

 

[dparm]

My 5,000 miles are a bit unusual...

-car isn't a DD and doesn't get driven for several days on end (I went 3 weeks last month without driving it)
-50/50 mix of stop-and-go city driving and highway trips
-sees WOT a lot, though never until the oil is warmed up
-autocrossed or tracked a few times a year


Agree that at $13/L and a 10L sump it kinda sucks but 5k is basically one year's use for me.

 

[dparm]

Was chatting with my brother who is a chemical engineer specializing in polymers. He doesn't necessarily think the high TAN is a bad thing -- the engine wear is good and the ester basestocks likely have a higher virgin TAN anyways.

He's no automotive expert but as a chemist he said there don't appear to be any problems caused by that TAN value.


I am still intrigued by this past discussion:
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1584125

TomNJ basically agreed with my brother and says the high TAN isn't a cause for concern since all the other values are in-check.

 

[bluesubie]

If wear goes up slightly with RLI, are you going to switch back to 300V or try RLI again?

-Dennis