2005 Infiniti G35 109533 miles - 5W30 - unknown brand

May 12, 2021
Recently purchased this vehicle, this is the analysis on the oil that was already in it. Looking for second opinions or suggestions on how to proceed.

Thank you in advance.

MAKE/MODEL: Nissan 3.5L V-6(VQ35DE)
FUEL TYPE: Gasoline(unleaded)
OIL TYPE & GRADE: Synthetic 5W30
OIL USE INTERVAL: 3905 miles

LEAD 144
ZINC 1142

SUS Viscosity @ 210°F 59.8
cSt Viscosity @ 100°C 10.16
Flashpoint in °F 435
Fuel % Antifreeze % 0
Water % 0
Insolubles % 0.3

Blackstone Labs said this:
There's quite a bit of metal in this sample. The averages show how this engine tends to wear after
4,800-mile intervals. If the interval on your sample is right (who knows for sure since you just bought it),
then some of this metal might be accumulation. Otherwise iron can show steel wear, with copper, lead, and
tin suggesting quite a bit of bearing wear. Some lead might be from leaded fuel, but with copper and tin also
showing up, there's a good chance at least some of this is from bearings. Monitor for low oil
pressure/engine noises. Check for air intake leaks (silicon).
Only 3905 total miles on this oil? Or did you put 3905 miles on the oil that was already in there?
according to the service records that i was provided with the car, that was how many miles were on the oil when I bought it, I purchased the car on 04/02/21 and the most recent oil change was done 01/30/20
You need to run it a known amount of miles on a known oil and re-test. Too much unknown here to draw a conclusion. No idea the driving style or the usage of the vehicle before you purchased it.
With silicon at 44... Makes me wonder if you have a ill fitted air filter ? Must be dirt entry from somewhere.... Or a really really inefficient air filter.

If the air filter is shot or you don't think it looks right or more importantly... It does not fit well and seal right...

Get the STP premium air filter from AutoZone. A very good air filter that uses fine test dust in the ISO 5011 test.

If there is free air leakage then needs to be rectified in my opinion.

Oil itself here looks just fine... Plenty of additives... And viscosity is still good and in range for a 5w30.

I have a VQ motor like yours. Mine now has 340,000+ miles on it.
There was a horribly dirty air filter when I purchased it. I replaced it when I along with the spark plugs and oil shortly after I purchased it. The intake has since been replaced with a z tube and pop charger filter
Well... What brand air filter ?

A new one let's in most of the silicon in it's first 10 percent usage life. Like it let's in 90 percent of the silicon in it's first 10 percent run time.

And if it's a very inefficient air filter.... That will be way, way worse than that.

At least the STP premium air filter is 98 percent using fine dust which is a far, far stronger and tougher test vs utilizing coarse dust in the test.

Make sure that z tube and everything is tight and right.

May possibly a good idea to utilize a smoke test to see if there is any pulling in of air into it.

Not a pretty report.

What is a "z tube" and "pop charger" air filter setup? Sounds like a K&N clone, in which case, efficiency is definitely not the name of the game.

Do you still have the old oil filter that came off it? Would be good to cut that open and see if it supports what we are seeing in this report.
I would do a couple of short OCI and see if you can flush out the metals. Also consider 0w40, it's worked well in other VQ motors.
I'd run Castrol 0w30 / 0w40 euro or M1 0w40 euro. I ran all my previous VQs on those oils for their entire life. The 4th gen maxima VQ30DE saw 185,000 when I sold it, my 350z saw 80k miles (all on castrol 0w40 / m1 0w40) .
I would almost bet on some serious bearing wear in that engine probably gone through the overlay. +1 on the 0w40 but another report like that would push me to do one of two things, flip it or open the engine to look at the bearings before they do crankshaft damage.
If there was ever a 0w40 engine this is it.
I don't know enough about used oil reports to have an opinion. But your engine is like that in my 2007 M35. I've had mine since it was new, and I find that it does fine with oil changes between 4500 and 5000 miles. I've used mostly Conoco Phillips (Kendall and 76) synthetic blends with a few full synthetic changes mixed in over 13 years. With little price difference now, I'm going with the SOPUS full synthetics (still 5w-30) and keeping the same interval. Good luck with your car. I love the engine in mine.
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I'd pretty much put nothing but 15w-40 in it like t4 and use a fram ultra to try to filter some crap and use a wix or Purolator air filter. I'd flush that engine first to try to remove some crap. A cheap thin oil with half a quart of naphtha for a half hour is enough. I'd also try to flush the very bottom of the pan. 2 quarts of gasoline left to sit there overnight will bust anything out but won't hurt a single thing as it's below the gasket.
Also you should check for hidden cracks in the two rubber intake hoses with the accordian look. Mine needed replacement at about 110K miles. Expensive parts, but you may be able to find some clones on eBay.