RLI BioSynXtra 15w-40 Low Ash, 9867mi, 1996 BMW M3

[d00df00d]

This is my second run on the low-ash version of RLI's 15w-40 heavy duty engine oil. I ran it longer this time and results are still good. By the end of the run, my car's OLM was at the end of the green zone (after which there is yellow and then red), which once again seems to be right on target given the oil's condition. I think I've found the oil I'll be sticking with for the rest of my time with this car.

I am completely baffled by the drop in fuel dilution. I did replace the spark plugs about 900 miles before drawing the sample, so maybe that did it. The car is still throwing ghost codes (i.e. no check-engine light) for a resistor in the ignition system and an O2 sensor, so... who knows.

The silver blip is probably from anti-seize from my friend's compression tester, which we used within 200 miles of pulling the sample.

According to RLI, sodium is NOT an additive in this oil and should not show up on the UOA. I don't know where it could be coming from other than coolant entering the combustion chamber in such a way that the water and glycol are burned off.


Summary of the OCI:

- Warm-ups have been less cautious than on previous OCIs. Once warm, the car is driven... hard. Let's just leave it at that.
- Mostly suburban and highway.
- Oil consumption accelerated to near 1 qt/1000 mi.
- Overall, the car runs well, but it's still a bit jerky on throttle transitions.


Report below. Middle column is the current sample; last column is the previous one.

Links to previous UOAs in order from most to least recent. Please note that the numbers from this UOA are NOT comparable with those from different labs:
RLI BioSynXtra 15w-40 HD Low Ash (first run)
RLI BioSynXtra 5w-40 HD (third run)
RLI BioSynXtra 5w-40 HD (first run)
RLI BioSyn SHP 0w-30
Motul 300V 5w-40 #2
Motul 300V 5w-40 #1
Motul 8100 X-Cess 5w-40

 

[dparm]

Any particular reason you chose the low ash version? Is yours the one with Nikasil liners?

 

[d00df00d]

No Nikasil liners here. I just figured that with my oil consumption, I'd want the add pack to be on the clean side.

 

[BMWTurboDzl]

I wonder what affect the oil consumption had on your results?You're pouring a lot of oil with that burn rate.

 

[OneEyeJack]

Can new clean add on oil repair the damage done to the oil left behind from blow by? Aren't the contaminants still there? Will the new oil just dilute the results?

 

[d00df00d]

Depends how the oil is being lost. If it's leaking, then adding new oil should be a net-positive. If it's being burned, then the new oil may or may not offset the damage and contamination.

That's my understanding...

 

[dparm]

And why did you switch from the 5w40?

 

[d00df00d]

I thought the lower VII content and better shear stability of the 15w-40 might help control my fuel dilution and oil consumption.

I selected the low ash variant for the reason I mentioned above.

 

[CATERHAM]

As most know this is not a true 15W-40. I think Bill W. has admitted it's a 5W-40, the 15W-40 grade labeling is for marketing purposes.
Both UOAs showed this oil to be considerably heavier, KV100 of 16cSt with the presence of fuel than the PDS spec' of 15.2cSt.
So this oil has either oxidizing quite a bit or the published KV100 spec' is not representative of what you're actually getting.

Based on what I've heard from regular RLI users I think it is the later. RLI has a lot of product variablity, if you really want to know what you've getting it's best to have a VOA done.

 

[OVERKILL]

Originally Posted By: CATERHAM
As most know this is not a true 15W-40. I think Bill W. has admitted it's a 5W-40, the 15W-40 grade labeling is for marketing purposes.
Both UOAs showed this oil to be considerably heavier, KV100 of 16cSt with the presence of fuel than the PDS spec' of 15.2cSt.
So this oil has either oxidizing quite a bit or the published KV100 spec' is not representative of what you're actually getting.

Based on what I've heard from regular RLI users I think it is the later. RLI has a lot of product variablity, if you really want to know what you've getting it's best to have a VOA done.



That's not all that confidence inspiring........

 

[CATERHAM]

I still like RLI a lot and wouldn't hesitate to run their oils in all my cars but it is a small company that offers a wide range of oil grades. When they say their PDS info is typical of what to expect that should be taken literally, they are very much just approximate figures.
This does not appear to be a quality control issue but rather one of "flexibility" from their point of view. It is one reason Bill does not want to provide more precise HTHSV figures.
You are likely to get a more representative oil if you buy one of their top line grades, such as their 0W-20, 0W-30 or 5W-40, but if you order their 5W-20, 5W-30, 10W-30 etc you may actually get something better such as their 0W-20 or 0W-30 without paying the higher price.

With regard to their 15W-40 diesel oil, anyone who orders it wants a heavy oil so if it turns out even heavier there really isn't a problem.
A VOA of this oil would likely have indicated it's a 50wt oil.