What weight oil over and over

[measureman]

I see a lot of posts asking what weight oil should I use.
Isn't that stamped on just about every oil fill cap?
Or in the owners manual.
Of course there are exceptions like real old cars or odd ball cars but very few drive those.

 

[tblt44]

75w 90 works for everything

 

[ZeeOSix]

If there could only be one oil viscosity in the world, it would most likely be 5W-30.

 

[nomas]

I see a lot of posts asking what weight oil should I use.
Isn't that stamped on just about every oil fill cap?
Or in the owners manual.
Of course there are exceptions like real old cars or odd ball cars but very few drive those.

You're kidding right ? You've been here long enough to know how it works around here .

 

[PimTac]

#1. A lot of people cannot read or even know what or where their owners manual is.

#2. Many people don’t even know where the oil cap is.

 

[CleanSump]

Those engineers that designed don't know diddly squat, the people that wrote the manuals are just marketers, and we know best because we read the MSDS for a trillion brands and make W... A.. Guesses.

 

[mahanddeem]

Maybe for the warranty duration, after that you're free to use whatever you use. It's your money.

 

[FordMan59]

10w40 has treated me right for the past 45 years and approximately 1M miles regardless of what the owners manual or oil cap says.

 

[Bill_W]

#1. A lot of people cannot read or even know what or where their owners manual is.

#2. Many people don’t even know where the oil cap is.

Oil cap viscosity are printed on Miata’s for Japan and North America only.

 

[CheezWhiz]

there are only so many things to talk about on a forum dedicated to motor oil. how many "liquid vs powder" threads per day do you reckon they must have on the kellyisthelaundrygirl forums?

 

[Bud]

Hey, it helps keep the forum alive.

 

[SR5]

This having the oil grade printed on the oil cap, and only having one grade in the owners manual, is a North American thing. Most of the world just have "oil" on the cap, and have a Temperature Vs Viscosity graph in the manual that lists a variety of grades.

My Nissan with the very common QR25DE engine, in the owners manual lists: 5W30, 5W40, 10W30, 10W40, 10W50, 15W40, 15W50, 20W40 and 20W50.

 

[Johnmpb]

Well Mr. Measureman,
It seems like a lot of people here seem to think they know better than the engineers that designed the cars. They will also use CAFE requirements to back up their claims and think that the auto manufacturers are out to get us all for better mpg figures. Lots of tin foil hat wearers

 

[SR5]

If there could only be one oil viscosity in the world, it would most likely be 5W-30.

There is a lot of truth to this, then the only decision would be:
- 5W30 with GF-6 and Dexos1 (low HTHS, mid SAPS)
- 5W30 with A3/B4 and MB 229.5 (high HTHS, high SAPS)
- 5W30 with C3 and VW 504/507 (high HTHS, low SAPS)
- etc

Still ample for many threads on BITOG

 

[Accent Abuser]

If there could only be one oil viscosity in the world, it would most likely be 5W-30.

Don't take away my 40!

 

[FordMan59]

My Nissan with the very common QR25DE engine, in the owners manual lists: 5W30, 5W40, 10W30, 10W40, 10W50, 15W40, 15W50, 20W40 and 20W50.View attachment 86699

My '16 Versa has a weight/temperature graph in it and also lists most if not all the weights you listed. The '88 Ford Escort I had for years listed 5w30 as the recommended oil. I used 10w40 in it summer and winter The engine had 518K miles without a rebuild when I finally retired it along about 2011 or 2012. There was no knocking and compression numbers were 145-155 across the board. Best I remember oil pressure was still around 40-45 PSI on a warm engine at 55-60 MPH.

 

[4WD]

Maybe for the warranty duration, after that you're free to use whatever you use. It's your money.

I resemble this - and built my stash around this thought process …
… allowed me to grab both 20’s and 30’s while premium lubes were on clearance …
(dual meaning of clearance stash)

 

[OM605]

Because 13 viscosities are listed in one of my owner's manuals, as an example. Oil caps just say "To avoid damage to engine, oil must not exceed MAX" and i've never a viscosity printed on an oil cap. Seems like it's an american thing only.

 

[RDY4WAR]

In bone stock engines with typical mild daily driver use, I completely agree with the OP.

If someone say replaces the factory turbo with a bigger one and ups the boost, puts in a new cam with stiffer valve springs and turns it 1,000 rpm higher, is in the military and getting relocated from Georgia to Alaska and never dealt with such cold starts, or anything else that deviates from the engine's intended use from the OEM, then that question is valid.

 

[Kuato]

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