ENGINE OIL best viscosity?

[CRYDR]

I brought my Z in for a 1st oil change. have 1,600 miles.
I requested a performance synthetic with a 20/40 V. They tried to convince me the 0/20 IS best. I tried to point out that we Live in South Florida where the temperatures are very hot most year round and that the oil pressure on my guage shows about 16 at idle and highest is about 30. Also stated the 0/20 is ok in colder Northern states. The final convincing stated to me was thar " IT IS REQUIRED" to maintain my warranty on the engine.
Am I incorrect in my belief ? What would be a viable solution for a better oil that would bring my oil pressure to a higher and in my oppinion, safer pressure?

 

[MacCool]

They designed and built the engine, and are on the hook for warranty coverage for 5 years. I'd just trust em'...

Maintenance section of the owner's manual...:

"-Genuine “NISSAN Motor Oil 0W-20 SP” (or equivalent) is recommended.
-If the above motor oil (or engine oil) is not available, a synthetic 0W-20 SP GF-6A motor oil (or engine oil) may be used.
-Damage caused by the use of motor oil (or engine oil) other than as recommended is not covered under NISSAN’s New Vehicle Limited Warranty."

 

[Jah_Happy]

My understanding is 0w-20 is best for fuel economy, probably fine for stock cars, but every tuner i talk to says 5w-30 or 40 is what we should be using if modified or spirited driving.

 

[MacCool]

I believe that it's common to overthink engine lubricating oils. If it wasn't, Andy Granatelli wouldn't have gotten so rich. and the Internet would lose about 1/3 of its traffic.

 

[ZillaZ]

I always stick with what the manual recommends but you are not going to kill your engine if you put in something a bit different. I have a small stock-pile of 5w30 and if I am in a pinch I will use it.

A lot of this stuff with oil how you should NEVER use different weights or you cant go from regular to synthetic and visa-vera is just scare tactics and marketing.

You *should* use what is recommended as thats's what they engineered it for. As others mentioned for warranty really. Engineers are not going run every engine they make 10k+ miles with different oil viscosities to see how everything holds up. That would be a lot of R&D and cost. They are going to stand behind what they have actually researched and tested and stand behind that.

Now if you have an old car with tons of miles on it and it's never had thinner or synthetic oil in it I personally would be wary of that cause you could develop a leak or some seepage but again, not going to kill your engine.

 

[TenneZ]

Do a UOA on the 0W-20 after 3k miles and see what the viscosity is after those miles. FWIW, I run 5W-30 in TN.

 

[Kelly1]

I would follow the manual or contact Nissan for alternate oil recommendations,rather than lose my warranty

 

[CRYDR]

I'm still a believer in my own theory as backed up by others and the racing industry. 0 viscosity in 100° weather is too thin. Oil pressure will drop and cause more damage than benefit. The owners manual is based on General ideas and does not factor in any variables. This would be fine in northern cooler temperatures but Not in southern like Florida, Arizona, Nevada where its always hottt. I will go with the dealer recommended no logic other than the corporate written manual.... For now! But going forward the second oil change will be to not kill my motor . "Jet Engine Mechanic"

 

[Jah_Happy]

I'm still a believer in my own theory as backed up by others and the racing industry. 0 viscosity in 100° weather is too thin. Oil pressure will drop and cause more damage than benefit. The owners manual is based on General ideas and does not factor in any variables. This would be fine in northern cooler temperatures but Not in southern like Florida, Arizona, Nevada where its always hottt. I will go with the dealer recommended no logic other than the corporate written manual.... For now! But going forward the second oil change will be to not kill my motor . "Jet Engine Mechanic"

Exactly, especially for anyone modified.

 

[Drago86]

I brought my Z in for a 1st oil change. have 1,600 miles.
I requested a performance synthetic with a 20/40 V. They tried to convince me the 0/20 IS best. I tried to point out that we Live in South Florida where the temperatures are very hot most year round and that the oil pressure on my guage shows about 16 at idle and highest is about 30. Also stated the 0/20 is ok in colder Northern states. The final convincing stated to me was thar " IT IS REQUIRED" to maintain my warranty on the engine.
Am I incorrect in my belief ? What would be a viable solution for a better oil that would bring my oil pressure to a higher and in my oppinion, safer pressure?

Just a note, increasing the viscosity won't do much to raise the idle/low engine rpm oil pressure much. These engines have an oil pressure relief solenoid that vents oil pressure at low engine speeds for better gas mileage.

I only know this because the q50/q60's share the same motor and the valve is prone to failing/sticking(keep up with oil changes!) which destroys the engine, see here: https://www.infinitiq50.org/threads/oem-q50-q60-3-0tt-oil-pump-control-solenoid.144149/

 

[Go2ZZZ]

AMS Oil 5W-30 or 5W-40 is best

 

[Go2ZZZ]

@MacCool what is so funny?

 

[Koryak]

I watch the oil temp more than pressure. Up to say 240 - 250 F is fine in hot weather while working the engine revs. Modern factory built engines have micro-finished crank journals which play well with 0W-20 oil. The metal peaks are lower so thick oil isn't needed to separate moving bearings.

The oil's SP spec is super important for the Z's direct injection with turbos to resist any tendency of low speed pre-ignition. Keeping the RPM up going uphill helps too

BTW, Nismo racing has a partnership with Motul for lubricants. Their tech rep or site product selector might be useful.

 

[thesilverbullet]

i use 10-30 in all my engines. do not trust oem - they have to deal with emissions, fuel milage and extreme weather conditions…. my ‘00+ cars & trucks call for 5-30, 5-20, 0-20 except for my honda s2k which called for 10-30. at the end of the day it probably does not matter for street cars - just my preference.

 

[Bert]

Stumbled across this the other day. Make of it what you will