Used Oil Analysis

[Sybaritic]

Hi Canadian friends, since my car is young like our livers once were in college or Uni, I decided to push things a little for experimentation, and kept Mobil 1 0W30 regular grade synthetic oil (as opposed to the extended performance version) in all winter from late Nov to early Apr. I went about 11,500km (never gone this long on any of my cars, so I hated myself near the end, but did it for science), and the report showed the oil had quite a bit of gas dilution, which might mean the engine runs rich most times, or just all the winter cold starts eventually got to the oil after over 10K.

Gasoline in oil is not ideal because it thins out it's slippery film, lowers viscosity over time and makes the oil acidic.

Conclusion I draw is it's probably better to follow their recommended interval, or do a change at 8,000km so it's a compromise between the severe and normal service schedules. In my personal opinion, 6,000km certainly doesn't hurt, but it seems like overkill since a change takes 7.2L, so there's tons of dirt-holding and detergent capacity, but care should be taken to change quicker in winter. I'll stick with an 8,000km change interval moving forward and use a good synthetic oil since it is a turbo engine too which runs under higher compression.

 

[eflyguy]

Higher fuel content is common if you are making many short trips or warming up vehicle without driving. Of course, if you're not driving enough for that to gas out, then changing more frequently is advised - which is why it's listed under the "severe operating conditions".

Blackstone includes notes with their analysis which covers any anomalies like this.

 

[RedCal]

You can get gas in the oil if you do lots of short trips, and don't allow the engine to heat up.
True story a friends work had an old pickup, it's only purpose was up and down the yard with supplies or a quick tow from one end to the other of the yard, it probably did 10km/year. They changed the oil 4 times a year because it was 50% gas in the oil pan due to the fact it never ran more that 5min at a time

 

[SafetyPilotCal]

7,000mi is about what I would expect to run a quality modern synthetic and filter for. Interesting to see gas dilution that high unless you make nothing but short trips or have extended idle periods. When I had a Blackstone report done on my E85 Regal with 3k miles on the change and 140k mi on the engine (changed it early just because I had just installed rockers and did the E85 conversion and wanted to make sure everything was kosher) and they showed a fuel dilution of less than 0.5. And that's with a tune that I know was pig rich for a while as I was trying to sort everything out.

Speaking of which, I just found two unused Blackstone test kits as I was packing stuff away. Next oil change I'll get a UOA done on the Stinger.

 

[Sybaritic]

The Interesting thing is no, I don’t do short jaunts, I have a commute that’s 30min, mostly highway w some traffic jams. On average, 60/40 hwy/arterial roads. But maybe over time, it weakened. I garage the car nightly too.

 

[RedCal]

The Interesting thing is no, I don’t do short jaunts, I have a commute that’s 30min, mostly highway w some traffic jams. On average, 60/40 hwy/arterial roads. But maybe over time, it weakened. I garage the car nightly too.

How long did you run the car before you took the sample? Most of the fuel in the oil would be from start up, you should take the car for a good 15+ min run before you take the sample - it will burn off any start up fuel that washed into the oil.

 

[Sybaritic]

How long did you run the car before you took the sample? Most of the fuel in the oil would be from start up, you should take the car for a good 15+ min run before you take the sample - it will burn off any start up fuel that washed into the oil.

Good Q. I came back from a 200km trip, waited 20min, then drained since it’s best to drain oil when warm/hot. I suspect maybe coupled w cold starts all winter and being a turbo engine, it’s a bit harder on oil. This is my first turbo car ever.

 

[Hockster]

Good info. I'll be going with the severe maintenance intervals. My current commute is only 6KM each way. Later this year that should change to ~45 each way.

 

[RedCal]

Good info. I'll be going with the severe maintenance intervals. My current commute is only 6KM each way. Later this year that should change to ~45 each way.

Except that you have a Stinger now... you will find ways to extend that 6km commute just so you can spend more time driving

 

[Hockster]

Except that you have a Stinger now... you will find ways to extend that 6km commute just so you can spend more time driving

Not really, industrial area with some real shitty roads. Direct route on the best one.

 

[RedCal]

Head south to YEG / Nisku, or keep going to Red Deer, then head back north

 

[Hockster]

I'm in Edmonton, east side. But did a run with my buddy yesterday, Leduc> Camrose> Wetaskiwin> home. 80Km/h winds though, made the out of car excursions miserable.