Using 5W-40 on Z's with no oil cooler
 

I received advice from a tuning shop to run 5W-40 oil as opposed to the 5W-30 since I don't have an oil cooler. They said the heavier will absorb the heat better and the heat will break down the 5W-40 viscosity to a lower weight. Is there any truth in this?

yes and no

Yes a w40 oil will be thicker at higher temperatures and protect better...

No 5w30 is fine for normal driving.

Do you think it would be detrimental at all to run 5w-40 during the summer months?

Could be...The VVEL system is pretty complex.....I'd stick with factory recommended viscosities.

Gotcha thanks!

:iagree: older cars or newer, more simple cars it won't matter what grade you run for most intents and purposes, but with such a complex motor as this one and many others these days, I'd stick to factory specs.

I'll stick with the recommended oil weight and the 3 yr Warranty can worry about the rest.

stick with 5w30 it should be ok. just watch the temp and check your oil every
fill up. here in texas the temp can go from 220 to 240 for no good reason.
it can be 85 or 100 outside. had my first oil change at 3000 am now at 5000
and have not used a drop of oil. i use mobil one.

Hello,

Since 2010, does anyone use 5w40 oil ? Nissan in the south of France recommend 5w40 oil instead of 5w30 due to the heat.
What about in california, Florida or Texas ? it's very hot there

I do only 5000 km (3100 miles) per year. I only drive on weekends but I often accelerate hard.

Just stick with a thicker 5w30 I would say. Motul EFE, Redline 5w30, M1 ESP 5w30 and PP Euro L 5w30 are available. They have a high HTHS rating (3.5, which is a good thing) and they run on the thicker side of a 30 grade oil.

I used Liquimoly 5w40 once, never had a issue, but I dumped out the next season without any ill effects.

thank you :driving:

In france, we don't have an extreme winter compared to USA or Canada. But I try 5w30 of mobil 1 :iagree:

I ran 5w40 with no issues before. I now run 5w50. It will work just fine.

Mobile 1 0w-40 Euro blend. Has everything you need.

I think 0w40 is for country where it's very cold, isn'it ?

It works for both. I use it in all of my vehicles.

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.

:rofl2::rofl2:
They can't even solve my problem with my keyfobs ...
and they did not see much nissan 350Z/370Z

I don't know how people drive in north america (smoother driving or aggressive driving) but in France many Z owners drive only on weekends (with aggressive driving :rofl2:).

I would use Mobil 1 5w30 Esp Formula :) because he have a high HTHS rating.

Why not just add an oil cooler, run factory rec 5w30 and not have to worry about excessive heat issues? Wife and I only ran M1 0w40 bc it was more track car than daily driver.

If you’re not tracking, then a 19 row oil cooler will be just fine, or even a 25 row. 34 row is only necessary if you’re gonna go to the track, or if you live in ME.

Exactly. I run a 19 Row out here in Toronto, it handles traffic, spirited driving coupled with hot weather just fine. I do not track hence the choice.

Going to W40 will not solve heat issue. Need oil cooler. W40 will just remain more viscous over 30 for a bit longer until it gets too hot and breaks down as well.

I know it can get hot in the South of France, but looking at historical data, July and Aug 2020 never went past 30c.

5W30 should take you way past 40c for a DD and spirited weekends, Specially if its a quality "true" synthetic oil. I'm sure Motul and Liqui-moly are available in France.

I will install an oil cooler in few month :)

I thought the 5w40 oil was an alternative to an oil cooler :D

In France, we have these oils (with hths >=3.5 mPa.s) :
- mobil 5w30 esp formula
- Motul 5w30 specific 17
- Liqui moly 5w30 (I don't know the best reference for 370z)

It has changed, it often takes 40 degrees :rofl2:

For information, we did not have the same speed limits, and I do not hesitate to drive at 160-170 km/h (105mph) for several hours. :driving:

Driving at a constant 160-170kph is actually beneficial. Should be good oil circulation and airflow. It's the stop and go or hill climbs and track style that will affect your temp. and oil.

From the 3 choices I'd go with Liqui-moly.

That Particular Motul is for Renault and the Mobil ESP is not a favorite but is ok.

Sheesh! Just use a high-quality oil with Nissan's specs for viz. Once you get up to operating temp, the difference in viz is negligible - the higher the temp the less the difference. The ECM will go into limp mode before things get hot enough to damage the oil.

I will take Abiogenic petroleum any day of the week. :tup:

If I could remember where I saw the testing I’d post it but they found the thick oil actually increased engine temps which makes a lot of sense as the pump has to work harder more pressure through the system. In the end their analysis was use the oil viscosity your engine was speced for. Personally I’ve used amsoil for years and it’s never let me down.

If you want to learn about oil in depth, go to bob is the oil guy. You can spend hours there looking at UOAs and VOAs of all the brand of oils and their viscosity. Talking about oil is mental masturbation and people will say this is the best and that is the best.

Here is the conclusion I have come to after spending hours on BITOG:

1) Not all oils are the same. A 5w30 synthetic oil vs a 5w30 syn oil with a Merc 229.5 and Porsche A40 approval are different. The latter will contain a higher HTHS rating, TBN and possibly more Zinc, Boron etc.

2) Some oils have a better BASE oil compared to other oils with the same viscosity, PAO, esters, hydrocracked etc. You have to read the data sheets to get a better idea and not all of the information is disclosed.

3) There are different groups of oils, I, II, III, IV and V. Some are blended together to get a good base stock. It is not unusual to blend group II and III together or group III with group IV, etc etc. It's chemistry simple as that. Better base oils usually contain PAO and Esters which give strong shear stability among other things

4) The BEST OIL is the oil you change on a REGULAR INTERVAL. Look for the approvals in your manual and change your oil AT LEAST once a year or every 8,000km or whatever comes first. I know some bottles say *up to* but that's if you have the ideal driving conditions, which many folk do not.

Anything you buy off the shelf that's "synthetic" (M1, Castrol, PP/Shell/QS) is good stuff and will give your car a happy life for everyday driving. There is a reasons why I placed synthetic in quotations, look at Castrol VS M1.

IF money is NO object to you and you could care less about what anyone says on a forum and you keep your oil changes to 8,000 km or less since you're against extended drain intervals. Go with Redline. I use their gears oils and they are fantastic, their oil is pricey but, it has Group IV and V (esters) and have great HTHS ratings and TBN. I've seen plenty of VOAs and UOAs and Redline always comes out stellar. However, I've seen M1 0W40 and Castrol 0w40, M1 ESP and PP Euro L UOAs and they come out stellar to, comparable to Redline for HALF the price if not more. . .

There is also the issue of LSPI, when to much calcium is introduced as a detergent, usually that's offset by Zinc and I think boron as well. Just put your nose to the books my friend and you will come to your own conclusion. Best of luck and enjoy the forums.