Now, I noticed your location is Israel; if you really are there, I'm not surprised your dealership is using a thicker oil due to the hotter temperatures there. Otherwise, there really isn't a good reason... people in California run 5W30... it's not a big deal.

So is the 5w40 also nissan ester oil or only the 5w30?

Nissan Ester Oil comes in a single weight, 5W30, as it was made specifically for the 370Z.

Purist, I know I am nagging but I talked to the dealership and the oil they use for the 370z is made by Nissan. They also use it on all their infinities. I'll get a pic of the bottle soon and post. It says 5w40, API SM/CF, and ACEA-A3/B4. The mobil 1 says API SM (no CF), ACEA-A3/B3 and ACEA-A3/B3. Now that you know where I live would you still recommend the 5w40 over the 0w40? The dealership claims the oil is from Nissan. Perhaps because of the different weight it is not easer based? What are your thoughts?

Pics of bottle

Based upon this image, this is still not the Nissan Ester Oil of which we speak.

https://www.mynismo.com/images_products/7589.jpg

This is what you're looking for. As far as I know, this particular oil doesn't actually come in the form of a 5L/5Qt jug, even for OEM use.

Purist, your picture isn't posted up properly. If I can't get the oil you speak of which would be better, the Mobil 1 0w40 or the Nissan 5w40 non ester? Try again the pic. Thanks

Shamrock, you're way too hung up on oil selection. Which type of oil is best is way, way, overstated in oil discussions. Use the oil recommended in your owner's manual and you can't go wrong, full stop. Guess who specified that oil? The guy who knows better than any forum discussion oil guru's - a Nissan engineer! There is no best oil because other than synthetic is better than dino but you pay a premium. Both oils will lubricate your engine without issue. It all comes down to personal preference. If you feel better having your maintenance performed by a Nissan dealer, then take their advice on oil selection. Now, quit worrying about oil and go enjoy your car.:driving:

Ultimately, he's right. Go with what is recommended. I can see the image just fine, so I don't know how else to show you.

I can only get here Nissan 5w40 which has no esters or Mobil 1 0w40. Which should I use? I thought the while point in Nissan oil was the esters.

Nissan has a few oils blended for them. It's just like how Pennzoil has their standard blend, a full synthetic blend, a long life blend, etc. Nissan happens to have their standard oils, then the Z-specific Ester blend. If your location limits you to only Nissan's standard 5W40 or Mobil 1 0W40, whichever one you pick is irrelevant. You will likely never see snow, although I don't doubt you will see colder temperatures. As a result, since your winter weights are mostly irrelevant, so go with whichever you prefer.

I would personally select Mobil 1 because it is considered to be a highly synthetic or fully synthetic oil. If I had any idea what Nissan used for their oil then I would actually have more of a choice to make.

If you really can't pick, just go with whatever the dealer gives you. Either way is good.

So it is a fact that although the oil 5w40 here is made by Nissan it has no esters? Only the 5w30 does? There is nothing on the bottle to tell me if there are esters?

It is likely that it has esters, but not enough to call it an ester oil. It is just as likely that it might have no esters at all. The viscosity of the oil doesn't have anything to do with what is in the oil.

Only the Nissan ESTER OIL has enough esters to be called an ester oil. This oil is made only for the Z and comes only in a single viscosity.

:facepalm:

A single viscosity oil would be for example a 30 where it stays that weight. A multiple viscosity oil is a 5w30 where the weight changes due to temperature.

Nissan Ester oil only has a small percentage of ester base in it where brands like Red Line is all pure Ester oil.