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.