RLI Biosyn 5W40, Audi RS4 update

[RI_RS4]

The original posting on the RLI Super High Performance Bio-Synthetic 5W40 HD oil is here:
]Double-Super-Secret 5W-40 Audi RS4 Racing Oil

Since then, quite a large number of UOAs have been performed, 80 UOAs, 20 RS4 engine, 610 to 53500 miles, 17 different Audi/VW 502/505 oils.

Here is a normalized Fe wear plot comparing Biosyn to other Audi approved oils. The last blue point and the last green point, at 38000 and 53000 miles respectively, were UOA samples taken on the same engine with Castrol TXT 5W40 and RLI Biosyn 5W40.

I'll let you all form your own conclusions.

measurement (Castrol TXT 5W40/RLI Biosyn 5W40)
miles on engine (38040/53500)
miles on oil (6000/10000)
Fe (33/26)
Sn (0/0)
Pb (2/3)
Cr (1/1)
Ni (1/1)
Al (10/10)
Si (6/6)
Na (15/10
100 cSt (10.7/12.2)
TAN (2.75/4.02)
Flash (305/250)
Nitration (12/13)
TBN (3.9/3.8)
VI (151/159)

 

[cheetahdriver]

i guess i have two questions,
(ok, i have a whole bunch, but only two that are important)

1. if you are looking at a change of 2.5ppm Fe vs ~5.5 Fe in long term usage, what does that translate out to in engine wear? that's a question that may or may not be answerable...but are you talking 200k vs 400k?

2. i know the Audi RS4 has some issues with a couple of things, do these numbers translate out into other engines with the same delta?

3 (ok, 3. shoot me) what was the OCI on these engines?

 

[RI_RS4]

1) that's 2.5 ppm per 1K miles and 5.5 ppm per 1K miles, in an engine with a 10 quart oil capacity. If the same wear was occurring in an engine with a 5 quart the sump capacity, all numbers would double. Assuming that it is an iron or steel part of the engine that fails first (cam chain, cams, rocker) in an all aluminum engine with low Al and bearing wear, then that should compute to better than double the usable engine life before major repair.

2) The numbers for Fe wear in engines that have fuel dilution seem to track.

3) It depends. OCI ranges from 3K to 10K. In the case of the last two data points, it was 6K and 10K respectively.

Note: 33 ppm of Fe wear in 6K miles seem like a small amount, but the engine has a 10 quart capacity. If the engine had a 4 quart capacity, the measured wear would be 80+ ppm in 6K miles.

 

[DmanWho]

Fascinating statistics.

(Popped using RLI)

How many Audi people are trying out the RLI?

 

[SubLGT]

% fuel was not measured?

 

[Audi Junkie]

Did you every try a VW 504 oil for the heck of it?

 

[glennc]

Those numbers seem generally high to me. Does this engine give unusually high Fe numbers? I tend to think of 2-3ppm/1k as being "typical," say 10-15ppm over a 5k interval - and that is with half the sump capacity, though also often half the cylinder count. Easy-wearing engines are often well below that, such as single-digit counts on 10k intervals and the like.

It's certainly very interesting. The data is almost too perfect. There is not a single other sample that even overlaps with the RLI samples.

 

[RI_RS4]

SubLGT - %fuel was measured, I just didn't type it in.

Audi Junkie - The factory oil is probably a 504 oil. It does not perform well either.

glennc - fuel dilution and multiple auxiliary and cam drive chains on an engine that revs to 8250 rpm eat seem to cause the high Fe wear. Thus far, every engine I've seen that has fuel dilution shows higher than usual Fe wear.

There is one sample that did overlap with the RLI UOA. It is factory oil taken out to 5K miles. Otherwise, you're correct. There is a distinct difference in the data for Fe. All other wear elementals are close to the same.

 

[Doc Mike]

Great great information.

I have a question though about the statistics.

I assume each data point is taken from an individual used oil analyis. What method was used to control for the mileage on the oil (not the mileage on the vehicle)? Obviously i'm getting at that we'd have to control for mileage on oil because you could have an average OCI of, say 6K miles for the vw502 oils and 3k miles for the RLI oils and that may account for any differences right there. Conversely it may be 3k miles for the RLI and 6K miles for the vw502 and it would make it even more powerful of results.

Thanks, Mike

 

[Eddie]

250 flash point is low. fuel dilution?

 

[RI_RS4]

Doc Mike,

Good to hear from you. We haven't talked in a while!

There are no controls on the UOAs. These are individual UOAs taken by individual owners. Some took multiple samples throughout the OCI, others took only one sample at the end of the OCI.

First of all, the data is normalized to wear per 1k Miles. This helps with the disparity in OCI length.

Here are a few statistics on the data:

502/505 Oil Samples

minimum Sample - 1086 miles
maximum Sample - 7000 miles
mean sample - 3045 miles
median sample - 2863 miles


RLI Oil Samples

minimum Sample - 1113 miles
maximum sample - 10000 miles
mean sample - 4599 miles
median sample - 4286 miles


All owners switched from 502/505 oil to RLI oil, because oil analysis showed higher fuel dilution, viscosity shear, and wear than was desired. In every case, RLI Biosyn showed better fuel dilution, viscosity shear, and wear than the previous oil at the same mileage, which allowed the owners to extend their OCI's.

In general, RLI oil stayed in the engine longer than previous 502/505 oils, and showed lower total wear at the oil change.

 

[RI_RS4]

Originally Posted By: Eddie
250 flash point is low. fuel dilution?


Yes, Audi FSI engines are fuel diluting monsters. This oil ran for 10K miles and showed 1.9% fuel. At 10K miles, acids had begun to rise and TBN was down to 3.8. More importantly, viscosity index had dropped from a VOA 180 to 159.

 

[RI_RS4]

Originally Posted By: DmanWho
Fascinating statistics.

(Popped using RLI)

How many Audi people are trying out the RLI?



There are 10 Audi owners I know that are using RLI right now.

 

[RI_RS4]

Originally Posted By: RI_RS4
Originally Posted By: DmanWho
Fascinating statistics.

(Popped using RLI)

How many Audi people are trying out the RLI?



There are 10 Audi owners I know that are using RLI right now.


About 1 out of 2 owners that use 502 oil and have their oil analyzed switch to RLI.

 

[RI_RS4]

Originally Posted By: Audi Junkie
Did you every try a VW 504 oil for the heck of it?


504 oils are primarily low sulfur and low ash. The factory oil is probably VW/Audi 504, but who knows.

Personally, once I found an oil that performed well (RLI Biosyn 5W40) it did not make sense to try a VW 504 oil for the "heck of it", in a $25K engine. There is at least one European owner that used Fuch Titan GT1 5W30, which is a 504 oil. It is included in the data and was unexceptional.

 

[SubLGT]

Originally Posted By: RI_RS4
Originally Posted By: Eddie
250 flash point is low. fuel dilution?


Yes, Audi FSI engines are fuel diluting monsters. This oil ran for 10K miles and showed 1.9% fuel. At 10K miles, acids had begun to rise and TBN was down to 3.8. More importantly, viscosity index had dropped from a VOA 180 to 159.


The Castrol 5W40 had a FP of 305. Was it better at keeping fuel out of the sump, than the RLI?

 

[RI_RS4]

The Castrol had 4000 less miles on it. It's really hard to compare FP or fuel % directly, unless you make the two runs under exactly the same conditions. I was able to do that with my engine. I also suspect that at 10K miles, the RLI was getting pretty well-worn, as evidenced by the reduced VI over VOA.

Here's an interesting plot of the RS4 engine data:

 

[bulwnkl]

RI_RS4, wasn't at least some of this data in the C-P & RLI presentation at STLE?

FWIW, we're seeing similar trends re: Fe wear in fuel diluters in our fleet so far when using BioSyn vs. 'conventional' fluids. Even with double the mileage on the oil, we'll get as little as half the Fe wear (even with noticeably higher fuel dilution). Our fleet is a somewhat mixed fleet of (mainly) pickups which tow heavy and hard from essentially cold start, and they often see short trips under these circumstances. We're VERY happy with the results so far.

 

[RI_RS4]

Originally Posted By: bulwnkl
RI_RS4, wasn't at least some of this data in the C-P & RLI presentation at STLE?

FWIW, we're seeing similar trends re: Fe wear in fuel diluters in our fleet so far when using BioSyn vs. 'conventional' fluids. Even with double the mileage on the oil, we'll get as little as half the Fe wear (even with noticeably higher fuel dilution). Our fleet is a somewhat mixed fleet of (mainly) pickups which tow heavy and hard from essentially cold start, and they often see short trips under these circumstances. We're VERY happy with the results so far.


Bulwnkl, yes, the first plot was part of the STLE presentation, although I've added a few additional data points.

Glad to hear that RLI is working well for your fleet as well. It's definitely a magic bullet for fuel diluters.

 

[buster]

Thanks for posting. Looks great.