SAE 10 motor oil?

[FCD]

My Capri's manual has a chart like many older cars on what oils to use depending on the temperature, i saw that it says to use anything from SAE 10 motor oil to 20w50, SAE 10 was only reccomended for places with sustained extreme cold temperatures, i don't ever remember seeing SAE 10W oil anywhere for sale?? next 10w30 and 10w40 are reccomended for mild to cold climates, then 20w40 and 20w50 are reccomended for hot climates

 

[A_Harman]

Technically, there is no such thing as SAE 10 motor oil, because the SAE has not defined a 10 high temperature grade.

They have defined low temperature grades, all denoted by a "W" following the number. OW, 5W, 10W, 15W, 20W, and 25W are all grades that could be formulated and approved by the API for sale as low temperature monogrades.

We have all gotten used to seeing multigrade oils such as 10W-30, and that means that the oil meets the cold flow viscosity requirements of a 10W monograde, and the high temperature viscosity requirements of a 30 monograde.

Before multigrade oils became commonplace, people would have to change their oil to run a 10W (for example) during cold weather, then change to run a 30 during warm weather. The SAE viscosity classification system has been around for over 100 years, but it wasn't until the 1950's that oil makers started producing multigrade oils.

 

[FCD]

Ah so it refers to a 10wXX oil not Straight 10

 

[Chris142]

Originally Posted By: FordCapriDriver
Ah so it refers to a 10wXX oil not Straight 10
No it would be a straight 10w. Probly has not been any made since the 70's or possibly earlier.

 

[Cardenio327]

Originally Posted By: Chris142
Originally Posted By: FordCapriDriver
Ah so it refers to a 10wXX oil not Straight 10
No it would be a straight 10w. Probly has not been any made since the 70's or possibly earlier.


^^This exactly^^

Hydraulic oils are sometimes labeled as 10w, but engine oils haven't been made in a long time as 10w.

A typical Chevrolet engine oil recommendation from the 1950s would suggest 10w for winter, 20w for spring & autumn, and straight 20 without the w for summer use.

There used to exist an engine oil called 20w-20 which had the viscosity of 20 when hot but behaved like a 20w when extremely cold.

 

[Atesz792]

Originally Posted By: Cardenio327

There used to exist an engine oil called 20w-20 which had the viscosity of 20 when hot but behaved like a 20w when extremely cold.

They still sell that around here. Not sure what people use it in, though.

 

[FCD]

If it hasn't been used since the 50s i wonder what it's doing in my 1975 Capri's owners manual, i do have a Haynes Manual from 1988 and there it specs 10w40,20w40 or 20w50, and 10w30 for cold climates, even though i know that the basic engine design of this engine did not change very much at all even though it was produced from 1965 , up until 2000 in South Africa where it was still used in Pickups , similar to Australia´s utes

 

[Gene K]

Interesting fact. A 15W with an HT/HS of 2.6+ is by definition also a 15W20.

 

[Shannow]

FCD, here's a pretty current Mercedes Benz sheet which shows how they would (currently/recently) limit the application of a 10W...note that it's curren't and that all of the monogrades have some specific ranges....that's their weakness, that was solved with multigrades.

Here's some typical looking specs for them, a Citgo sheet
http://www.technologylubricants.com/MSDS/CITGO/PDS/C500 single visc_pds.pdf

the 10W would/could, with the changes in J300 be labelled "10W16".

But good luck finding a 10W with any sort of modern petrol engine rating.

 

[Ignatz]

I remember using straight 10w in my 58 VW back in the early 70's.
Real cold winter and a 6 volt starter..the 10wt oil was great. And those were oil cans opened with a can opener. Don't remember seeing that oil since.

 

[meborder]

The only way I have seen a 10w monograde oil is in the non-detergent variety intended for air compressors and such.

I bought a quart 2 years ago when I was trying to get my air compressor to start better in the frigid cold.

It worked, btw.

But I wouldn't use that oil on a car.

 

[FCD]

I can't imagine a 70s Straight 10 oil giving great hot protection right

 

[cmhj]

Recall using it 50-60 years ago.