5w/20 oil OK to use?

d.

Well-known member
yes I am hanging on... I have several cases of 5w/20 left over from a modern car we sold.
Can I use it in my Model A, unknown history, runs well, no smoking?
Should I blend it with straight 30w, or is it OK on its own? Maybe a little STP additive?
 
i wouldnt use it or mix it with anything to use it.
if you were close by i would take it off your hands, as many newer cars spec for that
 
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I'd use it maybe with some viscosity stabiliser added to make it more viscous. It is no doubt of higher specs than what a Model A needs (as are all of the modern oils.)
Although it is much thinner than what most of us use, it no doubt would keep the metal components apart.
When building a high performance motor, it is important to have as much oil flowing through the bearings as possible (to cool them). Might even find that it is better than thick oil. It is worth noting that oil film strength is not so closely related to viscosity as it used to be because of the additives they put in there nowadays.
I bet I get lots of feedback on that one!!!
 
Why not use it in your 'modern' cars ? Most cars within the past decade call for that [ if not full syn].
I wouldn't use it in an 'A'.
I also don't believe in additives like STP or mixing oils.
 
When its hot its all the same,its thin when cold(great for startup) Pete

http://www.bobistheoilguy.com/motor-oil-101/

I'm not a smart man but I do know that the 5W20 specd for newer cars pours like water and the 15W40 is more viscous. This leads me to think the thicker oil would do a better job filling the gap between moving parts when running and not drain away when the engine is shut down.

I can imagine late model engines can get away with thinner oil due to tighter clearances and a better oiling system than engines that were designed in early 1900's.

I have to agree with most of the responders to this thread - Use the 5W20 in newer cars as called for by the engine designers.
 
Modern low end multi-viscosity oils enable new car makers to achieve the MPG figures required by Gov.
In an A, I use SAE 30HD. I would switch to SAE 20 HD if cold weather
usage is planned.
Old timers who came into our family Texaco in the 1950's used SAE 20
year 'round in southern New England.
Rocketsled
 
Opps!! Being stupid is not against the law! It's mighty unhandy once in a while:o Pete

I think the guy who came up with the "system" should be shot! there are far easier ways, that would be easier to "get".

MOST people (inc mechanics and piles of people on here) still don't understand it (even if they think they do ;) )
 
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