20k Oil Analysis

[TK42one]

Completed my 20k oil analysis. I went 8k between changes on this one and the oxidation value was high. Over this 8k interval there was about 4k of towing and higher speed driving.

 

[Tazzieman]

Oil analysis seems to be a very NA thing. Just an observation from someone downunder.

 

[NQ94]

Oil analysis seems to be a very NA thing. Just an observation from someone downunder.

People are aware of it in Australia , they just don't want to pay the extra or believe sampling a small sump capacity is not worth while. Service departments really don't like or understand oil analysis as a diagnostic tool.
Sample the new product being used and compare it against the used oil results.

 

[Tazzieman]

And what do you do if your car blood test is a bit off? Avoid future bad habits and get more exercise? Or add green tea?

 

[Clark Kent]

I'm a fan. It's less common in Australia so there are less oil labs doing it and the price is higher.

The most accessible benefit to the engaged owner is that it informs decisions about oil change intervals. With modern 0W-xx oils, lab analysis results point towards doing shorter intervals if you want to maximise the protection the oil provides to your engine. Long intervals look good on a sales brochure but combined with enviro-marketed oils your engine life and durability are being impacted. Doing more frequent oil changes removes circulating contaminants, restores the oil chemistry and replaces the additives package.
My vehicle is not worked hard and I do a lot of short trips so I've switched to doing an intermediate oil-only change at 7,500km as well as the scheduled oil and filter change every 15,000km.
Surface filters (pleated media) work better with a light debris loading. A new oil filter element improves with use hence it can go the full 15,000km.

 

[NQ94]

And what do you do if your car blood test is a bit off? Avoid future bad habits and get more exercise? Or add green tea?

Load it up with more medication and order more expensive tests like the GP does.

In all seriousness with these expesive cars with expensive engines an occasional oil sample report can be helpful to encourage DIY owners to investigate around the engine, find and repair or let the dealer know about some of the problems.
For example using the sample provided oxidisation is high, this is directly related to how the vehicle was used high speed and 50% heavy towing. Fuel usage was higher, higher cylinder pressure and temperatures would of been sustained longer. Sump temps may of looked ok but the oil is getting pummelled cooling the piston crowns in a turbo engine. The solution would be an earlier oil change.
The elevated sodium check resivior levels for unexplained coolant loss. However, some oils contain sodium as part of the additive package (Penrite) so also check potassium levels. This is good reason to sample the new oil product being used and not chop and change oil brands every service. Sodium can be also used as an ingredient in some fuel additives.
Partical count for metals is material from break in and wear. In a new engines depending on how it is worked this may take some time to stabilise. If there is a sudden unexplained rise time to pull covers and investigate.
Silicon, even though not an issue on this sample in a 4x4 used in dusty environments silicon is common, a very good item to monitor and in most cases easy to fix. In a new engine first sample high silicon is likely to be mainly sealants and lubricants used during assembly. As the engine ages sudden spikes in silicon are a good sign of dust ingress from poorly sealed intake systems, crankcase ventilation or major oil leaks around the engine.
Fuel dilution is a good one to check. It could mean fuel system leaks or bad injectors or on some engines excessive DPF burn cycles. Around 5% fuel in oil can start the failure of plain bearings like big ends and mains pushing 10% and above can cause some engines to fail.
A car is just a dumb lump of metal that's easier to fix from an oil sample report then us with a blood test report, a Bex and a lie down.

 

[255/85]

The lab isn't giving you normal values to compare your results to so I'd just follow their advice and change the oil more often. I've used Blackstone a time or two and they provide comparison numbers based on their previous tests of the same engine type.

 

[Tazzieman]

The lab isn't giving you normal values to compare your results to so I'd just follow their advice and change the oil more often.

Even as a stduent in the early 80s I never skimped on regular oil changes. And shorter intervals for harder usage periods.
Prenentative maintenance, like exercise and a good diet
Pay now or pay later.

 

[landmannnn]

Many years ago I used to run a fleet of Mercedes trucks. The cost of oil analysis (£30) wasn't much considering the 50 or so litres of synthetic oil. I can remember one truck doing over 200,000 miles before analysis said it needed an oil change.

As @NQ94 says, a useful tool for identifying any mechanical issues long before any symptoms show.

 

[NQ94]

Many years ago I used to run a fleet of Mercedes trucks. The cost of oil analysis (£30) wasn't much considering the 50 or so litres of synthetic oil. I can remember one truck doing over 200,000 miles before analysis said it needed an oil change.

As @NQ94 says, a useful tool for identifying any mechanical issues long before any symptoms show.

When I worked for an OEM engine company we were doing similar tests early 2000s to extend oil change intervals for Australian conditions comparing road train, B double and single trailer prime movers. This is when companies started developing oil change intervals based on fuel burn and duty cycle. The standard was about 25000km intervals then we started to see 80000 to 100000km intervals for some applications during the tests.

 

[Tenac]

You can use oil analysis to determine many things actually. In some of my race applications it was a good use to understand the wear, temp tolerance and more. Typically when I think of someone using it on a daily it is just to simply check to see if the oil is meeting the standard they are telling us they are meeting. Often you can send a sample of the oil as when it was new and then the changed oil and the comparison is what is used to determine if the cleaning agents are working, what the break down is of the oil etc. Actually if I'm not wrong here GM is facing some really big challenges with some of their 6.2L engines due to oil not meeting the standard they specced to customers that have early engine failure.

 

[NQ94]

You can use oil analysis to determine many things actually. In some of my race applications it was a good use to understand the wear, temp tolerance and more. Typically when I think of someone using it on a daily it is just to simply check to see if the oil is meeting the standard they are telling us they are meeting. Often you can send a sample of the oil as when it was new and then the changed oil and the comparison is what is used to determine if the cleaning agents are working, what the break down is of the oil etc. Actually if I'm not wrong here GM is facing some really big challenges with some of their 6.2L engines due to oil not meeting the standard they specced to customers that have early engine failure.

I have sampled several brands of new oils straight from the bottle to get a base reading and just to compare brands for a project. Interesting how close some brands are to each other and how much an oil companies made for OEM brand can to their retail brands. In the 0W-20 oil and 5W-30 there can variances between additives in different batches of the same brands. In the new oil samples 5W-30 has more leeway in viscosity variance between the brands while the different brands of 0W-20 oils are pretty close in viscosity while meeting the set standards. The other noticeable difference was the detergent quantities used. Magnesium and Calcium quantities vary considerably between brands and if the oil is purely for diesel engines or for both petrol and diesel engines.
GM uses it's own DEXOS standards for their oil which has their own in-house developed tests and is a breakaway from the two more costly international standards ACEA and SAE. It would be interesting to see if an oil sample trend would of picked up an imminent engine failure in the GM 6.2 engines.
In Australia they sell RHD converted 1500 Chev pickups but you don't hear to much about engine failures even with the engine recall active in Australia. Not sure if they have changed oil viscosities for Australia as most of the RHD converted US utes are heavily marketed towards towing.

 

[255/85]

The half ton pickup market is fairly broad in the States. Towing, yes, but also performance and a dozen other uses. They are quite literally on every street corner. I would think that the cost of ownership in Australia would tend to make owners reluctant to be as cavalier as we are here. It's not uncommon to see someone with a brand new truck start up and drive off without letting the engine warm up or even build oil pressure.

 

[Tenac]

Yeah it could just be the sample size impact of how many are out there. Heck it could just be the batch or a batch of production that was really impacted.