It’s been a minute, this is the only mobile 1 oil that’s actually a true synthetic right? Also stock GTR fill as well. If so, that’s what we used for a total of 6 years and shitloads of track days (plus 34 row oil cooler). That oil if it’s the one we used runs “thin” for a 40 weight so it’s fine,a very good oil choice that is available everywhere like Wally World. :tup:

My 2 Hemi's spec a 0w-20 oil. I switched to the 0w-40 in both. The Hemi tick in the truck quieted down.

Running one grade higher or lower in reality won't hurt anything. The _W number will make the most noticeable difference for cold weather.

Oil is designed to be at around 212F or 100C regularly. If you run a 40grade oil instead of a 30grade the temps need to be at around 239F or 115C regularly to achieve the same viscosity. Question is why would you want to run at higher temps regularly, heat makes everything worse in an engine.
https://www.penriteoil.com.au/assets...mgs/aSZ9QeGTRj

I did switch to 5W-40 right before track events and change it out after.

We both know that 0w-20 is emission oil. It does nothing for longevity of the engine.

fify

Factory spec is safest. Nissan will have a bunch of lubrication engineers who have settled on the "most correct" viscosity for a wide range of reasons. But as Spooler said there are also regulatory hoops to jump through so "reasons" doesn't just mean driving conditions. If a 5W20 oil and a 5W40 oil both work fine but emissions is better with the former, then 5W20 or 5W30 will be specified and 5W40 will get dismissed.

Look at 2011Nismo's graph a couple of posts up. The VVEL system has to work with 5W30 oil that has a viscosity of 50 at 40 degrees C. At 0 degrees C the viscosity will be 100+ and the VVEL still has to function (at least under low engine stress, to idle the car and drive gently until oil temperature improves). I could fill my car with 5W30 and flog it as soon as the oil temp needle has started to come up, at 80C 5W30 oil has the same viscosity as 5W40 does at 100C.

There is some truth in "thicker oil provides more protection at high temperature" and "thinner oil flows better so it removes heat well" and so on. But unless you are building a 1000hp beast or spend most of your time above 5000RPM it matters a lot less than you think. I used to spend a good half hour staring at the oil aisle before making a decision but the fact my engine didn't blow up doesn't mean fussing over it that much was justified :)

Swapped to M1 0W40 on the Z a couple years ago and Blackstone reports have been great.
40k miles or so but heavy track use.

It should be a fairly safe swap from 5W30 to 0W40 for most cars.

It’s not a “true” synthetic (group IV AND V oils) however it’s a mix of GTL and PAO, and can be labelled as a synthetic as per rules and regulation in the US and Canada (refer to M1 vs Castrol battle regarding the term “synthetic”. Still it’s a phenomenal oil and I run it in my euro car and many others run it in numerous other situations with stellar results. The Z does very well with this oil also! Many use it with great results. The oil has a HTHS of 3.6 and a TBN greater than 10 so it can be used for long intervals.

I live in Paris. Winter is not a problem because it never gets below -5C (40F). I think 5WXX oil is ok for me.
The problem it's when my engine is hot. Engine oil is often at 110-115 degrees in traffic or sporty driving. I often drive on roads without speed limits (at germany :driving:).

This is why I would like to know if it is good for engine to drive with 5w40 oil throughout the year. :)

It will be fine. You will have no issues.

Nissan (and all other car makers) engineers spend at least a little bit of time and money figuring out which oil viz works best in each engine. Plus they have a lot of experience. And engines are a LOT pickier than they were back in The Good Old Days of iron blocks and carburetors. I'll go with what they recommend. ;)

But, as mentioned above, a few cSt here or there on the W end isn't going to make that much difference. But you can go too far.

Nissan dealer in south of France recommend 5w40.

I was a little surprised because all people in this forum recommended 5w30 oil, despite the high temperatures in summer in the United States.

I discussed with some owners in France, most use 5w40. But we aren’t many to have a feedback on the reliability of the engine with this oil.

:iagree:

I track with 0w-40. :driving:

How many auto engine engineers work at the dealership?

As the chart above shows, once the temp gets over 100C or so, the difference in viscosity is very little and which viz you use is not that important.
Below about 60C, the difference in viz can cause higher pressure, more strain on the oil pump, and a little less flow through the system. Moving up 10 probably won't make much differerence unless you really push the engine when cold, but why risk it.

This is for DDs. You track guys operate under different conditions.

Turbo guys too. My engine builder recommended 5w50 or 15w50. I run 5w50.