Infiniti Q50 (VR30DDTT) | can't make up my mind on oil...

The oil is sensitive to the quality of the gasoline? How so?
sulfur in gasoline can create sulfuric acid in the sump, reducing TBN, so if running low saps oil, all it means is that it has to be changed a lot more often. I could probably still get away with once a year oil change running low saps oil but I feel "safer" with something like PP 5w30.
 
I would not use ANY information on that web site.
We've got posts here on BITOG where people state that PP 'can' be used longer but either way it goes my situation is different, I don't drive this car enough to change oil twice a year, so keeping my engine clean and well protected is what matters to me. I really don't think changing oil twice a year would offer any more protection given that I drove 1800 mi since I changed it last time.
 
sulfur in gasoline can create sulfuric acid in the sump, reducing TBN, so if running low saps oil, all it means is that it has to be changed a lot more often. I could probably still get away with once a year oil change running low saps oil but I feel "safer" with something like PP 5w30.
Yes I understand the chemistry. Actually it’s the mixed sulfur oxides from the products of combustion that when combined with water cause the acid. How much are you driving during this period? Oil that is just sitting in the sump does not become progressively more acidic unless the vehicle is being driven. Especially multiple short trips.

Nevertheless if that’s your major concern then I would use Mobil 1 EP. Go by what they manufacturer guarantees rather than goofy information on some website. Most European oils such as Mobil 1 0W-40 and the Castrol equivalent have long-drain approvals as well.
 
Especially multiple short trips.

Nevertheless if that’s your major concern then I would use Mobil 1 EP. Go by what they manufacturer guarantees rather than goofy information on some website
Yes, the 1,800 miles that I drove since last August were all short trips. That's the thing, the manufacturer doesn't really recommend anything but 0w20 Nissan oil or any other api sn approved oil. As to how often I should change it, I believe Infiniti recommends changing it whenever the car is telling me to do so, which is like 10k miles and I'm not doing that LOL neither would I use 0w20 where I am. BITOG is always my main source of info but to be able to think critically, I do refer to other sources from time to time. That website above just provided basic difference between PP and Valvoline advanced and no matter where I go, for the most part, it seems like PP is what most people choose over Valvoline Advanced.

You're not the first one to suggest m1 ep so I'll start researching that. Only thing I can say about it now is that it is almost twice more expensive than PP.

Update: sooo, no more POA it appears in M1 5w30 ep? Hmm.... I may not benefit from running this in my twin turbo gdi engine then.
 
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Yes, the 1,800 miles that I drove since last August were all short trips. That's the thing, the manufacturer doesn't really recommend anything but 0w20 Nissan oil or any other api sn approved oil. As to how often I should change it, I believe Infiniti recommends changing it whenever the car is telling me to do so, which is like 10k miles and I'm not doing that LOL neither would I use 0w20 where I am. BITOG is always my main source of info but to be able to think critically, I do refer to other sources from time to time. That website above just provided basic difference between PP and Valvoline advanced and no matter where I go, for the most part, it seems like PP is what most people choose over Valvoline Advanced.

You're not the first one to suggest m1 ep so I'll start researching that. Only thing I can say about it now is that it is almost twice more expensive than PP.

Update: sooo, no more POA it appears in M1 5w30 ep? Hmm.... I may not benefit from running this in my twin turbo gdi engine then.
Well you weren't going to get PAO in any of the other oils you were looking at either, lol.

You want something with a lot of PAO in it you are spending a lot more money, you'll have to look at Ravenol if you want something with approvals, or, if that's less of a concern, you can look at HPL and AMSOIL SS.
 
I know this, but PP doesn't cost as much as M1 ep does.
And PP isn't additized to handle extended drains like M1 EP is. So you need to figure out what you want. Personally, I'd just run M1 0W-40 unless you are absolutely drinking oil. Lots of Euro high performance sedans had a real drinking habit running full-SAPS oils and catalyst failure was never a big thing to come out of it. In fact, the most catalysts I've seen failed are on engines that are short tripped and driven like there's an egg under the pedal.
 
Both tunes use the same VD30DDTT engine and recommend 0w20 oil.

This particular engine runs the oil at 160-180f and with other provisions in place can accommodate low viscosity oil.

If HTHS was the main concern, why not use a 25w60 oils with high hths values?
because there has ot be a reasonable limit to viscosity sometime..
And if the engine was always so good at keeping oil temps constant we indeed would not need good HTHS values.

Incidentally I struggle to believe those numbers.
Where were they measured?
My old Passat naturally aspirated 2.8L VR6 ran approx 220F oil temp fully warmed up and in summer up a hill it was no problem to get it to 232F.
I do not believe a turboed engine where the oil runs thru a turbo that is powered by exhaust cases(!!!) runs as cool as 160-80F.
Those are transmission ATF numbers
Incidentally that mid 90s Passat V6 recommended 15w-40 for winter (15w is actually quite thin. Remember a straight 20 weight oil used to be a winter fill until multi vis oils came along.. and now people say a 5w-40 is too thick , laughter) and 20w-50 for summer.
 
It's worth talking about it because I drive 2k miles/year or less for almost 3 years now, so it's important that I make the right decision when it comes to oil. I feel like changing it twice a year is just a waste of money, heck, when I did my last oil change last August, the oil looked new and didn't even smell like gas.

In my Kia's case I always change at 5k mi or 6 months, whichever comes first and before I installed a catch can, I've been baking my intake valves with Valvoline 5w30 advanced. They were so filthy that I spent half a day scrubbing them last year. I experienced rough idle and horrible gas mileage. It took me 20 minutes to remove the intake manifold (which was btw covered with gunk on the inside). After cleaning everything, I then installed a catch can, which fills up quickly during winter. Nevertheless, NO WAY it will take 20 minutes to remove the manifold on my VR and quite honestly I don't even want to do it any time soon (or until I have no warranty). You know that all these valve cleaners don't do a thing since our valves don't get washed, so I don't use them. I'd much rather take preventive measures to avoid my VR's valves from baking and one way to do this is by using low saps oil. And before BITOG experts attempt to bite me in the ass again, I'm not saying that low saps oil is the cure from CDB on the valves, it will still happen just less of it and throughout longer period of time. I mean, I speak with these people that run that oil on a daily basis. Yes, they live in Europe and yes they use it in their q50 and q60 with the same VR engine. No, they won't come here to confirm my words and I don't expect anyone to believe me anyway.

Bottom line is, it was hard for me to believe it the first time we spoke about it about 6 months ago or so but now that my annual OC is coming up, I want to be sure the oil I select is good in terms of protection, "lower" on saps and is OK to change once a year given that I drive ~2k miles in traffic making short trips. Valvoline suggests changing every 5k miles or per manufacturer's recommendation while PP can allows extended drain intervals, which is my case in terms of time but not the miles. From spending hours and hours here on BITOG and other sources, I think Pennzoil Platinum is the oil to use (I was gonna go with Pennzoil Platinum Euro L but that thing has too little moly in it (~60 ppm?) and plus, it seems like that oil is sensitive to the quality of gasoline and since I fill up at Sam's or Costco, I don't have any data about the quality of gas they sell).
If you just hit it with a spray cleaner every 10k you won't have to do that.
 
If you just hit it with a spray cleaner every 10k you won't have to do that.

I don't trust these sprays a whole lot. There are lots of horror stories out there where people clog their cats after those sprays. You can also introduce CD particles inside the cylinders with a possibility of scratching the cylinder walls. I've used lucas GDI cleaner but I soaked each valve while it was in closed position (i.e. I did not follow the instructions on the back of the can) and then sucked it all out using a shop vac after scrubbing just a bit. They want you to keep the RPMs at around 2500 while spraying hoping that whatever the spray removes to burn off in the combustion chamber. Yeah, it doesn't always work that way to say the least. The only safest and effective way to clean intake valves on a GDI motor is by walnut blasting them and that service ain't cheap.
 
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