Engine Oil testing - soot levels

[jesteh]

Decided to do an oil test on 4 year old T6 with Miller Oils at 12k miles after 12 months (long life oil supplied by VW). Reason for testing was to check if I need to do oil change before Christmas (busy time)

Test came back with soot at 2.7% with advisory to change oil immediately. All other measurements were OK, little bit low on viscosity but well within expectation.

Any idea how concerned I should be about this? Could this be the consequence of how I took the oil sample? I took a sample on cold engine using thin plastic tube pushed through the dipstick guide. I assume the tube reached the bottom of the oil pan and possibly sucked up all the crud that settled there.

 

[DXX]

A hot oil sample is alway better but having spent £50 and getting a bad result you really should act on it otherwise it’s not worth doing the test in the first place.
Soot will be deposited in the oil control rings and once they are gummed up it’s game over.
The lowered viscosity can really only be fuel dilution, you should have a figure for that in the results.
IMO and many others the Longlife service interval is just a means of making a commercial vehicle more attractive to a fleet operator. It may operate without issues for 5 years and then fail when sold on to the next owner. Synthetic oil is capable of the service hours, it’s just the soot and fuel contamination the accumulates in that time.

An oil and filter change shouldn’t take any longer than an hour so I can’t see it affecting Christmas.

 

[jesteh]

Thanks, I appreciate that there is no time to waste now, I will change it tomorrow. I was more interested what is the long term impact of soot being high until now
Also, fuel dilution was just under 1.5% which is considered good enough level.

 

[DXX]

Also, fuel dilution was just under 1.5% which is considered good enough level.

2% is the threshold for Caution so it’s definitely time to change.

 

[jesteh]

Any thoughts of whether I damaged the engine with it running so high on soot?

 

[DXX]

Any thoughts of whether I damaged the engine with it running so high on soot?

A Caution level is around 1%, 2.7% is pretty high but what’s done is done. It might indicate that the EGR is not sealing and there is a constant flow AND / OR there are too many failed DPF re-generations. Maybe consider reducing the oil change interval to less than 12K miles.
As a comparison I have a CFCA that was at 0.2% soot after 5K miles.