Thread: UOA: Used oil analysis thread

GC is only in 0-w30 iirc. Other syntecs are not GC. I have GC in my VE right now.

I use the regular castrol syntec.
I didn't know the ve would work well with 0w-30, what are the advantages if any for running that oil? How often do you change it? What's your driving style?

I drive almost all highway with some high rpm in the city, and put 6000 miles on the ve in 4-5 weeks.

not sure about vvl but I know the bmw vanos system has to have the right oil or it doesn't function properly. Not sure if the winter weight would affect things much tbh. As long as it's warm weight is right.

When I bought my B14 in 1997, I was driving 200 miles per day with about 75% over 70 mph (after break-in). My lab report on Castrol Syntec 5w-30 showed a low viscosity, so I started blending in some 5w-50. By the time I got to 300,000 miles, I was using all 5w-50.

On my new VE car I get plenty of oil pressure at startup according to my gauge so that was my main concern w/ the 0 weight when cold. When its warm the GC is actually almost up to 40w spec but understanding that is a lot of technical oil jargon.

On my last VE I had my change interval around 3k usually but the UOA said I could up it considerably. When I pulled that VE motor and disassembled it it was significantly cleaner than when I had bought it. There were no signs of wear and it was a healthy runner. 182whp and up to 36mpg hwy.

GC is just really good oil. The 5w and 10w syntec isn't the German stuff so I run the 0 weight.

I am a little concerned with "normal" wear rates on the Mobil 1. I mean, if you are paying 2x the cost for the synthetic... you should have better than "normal" results. Otherwise, I would just switch back to a non-synth.

Or you could just buy an oil that is, uh... good. Yeah. That's the word.

Comparing the Castrol syn results, it looks pretty close to my Mobil one results after 200k miles. The one exception is the magnesium which is massively higher in the Castrol syn numbers, but I'm guessing more of the VE internals are magnesium than a DE's are?

I wish more people would post up their UOAs with different oils and engines so we could have first hand results to compare oils...

I will be posting 5W-30 G-Oil after 5k miles of normal use very shortly.
I thought it would be nice to start using a bio-degradable oil.

G-Oil Info

I've been looking for my Castrol results and I can't find them. Sorry.


I only can find the initial one I took on the VE motor. In this case the car had good numbers because the RP would slip through the pcv or somewhere and eaten in immense quantities. One night of drag racing would move the level almost to the low mark on the dipstick. That only happened once but if you have to constantly add oil of course its going to have a good UOA... RP is crap imo.



Here is one from my 200sx. That was a sweet car even though it was a 98 extremely clean. This was w/0w-30 GC... probably overkill for a stock motor w/ only HS short intake but it got 34+ MPG on the highway and I paid for almost the whole car getting 50-55 cents cents per mile on my expenses so the oil was one small cost out of that.

This is my UOA of M-1 that came on my VE. The elevated titanium I think is from the Brian Crower springs and retainers. The report says it is 5w-20 which I was surprised, but I didn't ask prev. owner what grade he used. Also he may have told me the miles on the oil but he wasn't sure. It was not a 4900 OCI. I would guess around 1500 miles on this oil.

Disregard the second two columns that's from my old 200sx and Blackstone assumed I was using that. I'm going to call them one of these days to see if I can't get a new copy of the UOA from my last VVL SE-R.