oil weight recommendations?

F

fordfrank

Junior Member
Sorry for what is probably a fairly simple question but I did check the archives and can't really find a clear answer anywhere. I'm changing out all the fluids in a 31 that I bought and am well into fixing.
My question at the moment is what weight oil should I be using. Because I don't find any specific recommendations anywhere, I'm thinking of 10-30. Thoughts?

Thanks for any ideas.
 
I believe Henry recommended 40wgt.. I use straight 30wgt in all the old stuff.. But, you'll get a lot of opinions, this is talked about a lot..
 
Ford recommended 20 weight for winter and 40 weight for summer use. I have never been able to find 20W40 . I use 20W50 I think that the 50 weight will be good and the engine will run quieter. I wouldn't want to run oil thinner than 20 weight. Just my thoughts, people will usually use what they like.
 
Shell Rotella 15W40 is available at every Walmart and PepBoys I have visited.
The original Ford guide said 20 weight in winter and 40 in summer, so the 212 degrees test as 40 works in summer, and the 15W is its rating at 32 degrees, F, so I figure its close to the 20 and the polymers are driving it to 40 wt spec at operating temps, PLUS it has a high percentage of ZDDP which some of us think is good for our engines.
 
Purdy Swoft said:
Ford recommended 20 weight for winter and 40 weight for summer use. I have never been able to find 20W40 . I use 20W50 I think that the 50 weight will be good and the engine will run quieter. I wouldn't want to run oil thinner than 20 weight. Just my thoughts, people will usually use what they like.
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Although i'm not sure how compatable it would be, I know for a fact Yamaha sells 20w40 without friction modifiers for ATV's as I use it in my one air cooled ATV.

Reason it does not have friction modifiers is the clutch has problems with them (wet clutch)

I'm not sure but I bet friction modifiers are something an 'A' engine either appreciates or needs. I'm betting 10w40 is fine in an A.
 
Bruce Adams said:
Shell Rotella 15W40 is available at every Walmart and PepBoys I have visited.
The original Ford guide said 20 weight in winter and 40 in summer, so the 212 degrees test as 40 works in summer, and the 15W is its rating at 32 degrees, F, so I figure its close to the 20 and the polymers are driving it to 40 wt spec at operating temps, PLUS it has a high percentage of ZDDP which some of us think is good for our engines.
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The percentage of ZDDP in Rotella has been reduced the same as car oils. It's no longer the oil to use. One of the few car oils left, other than racing oils, to have over 1100ppm ZDDP is Kendall 20-50. However, if your engine is stock and original as Henry intended, you dont need the high levels of ZDDP. ZDDP only started being introduced into oil after the war when the new-fangled ohv V8s with their high valve spring pressures were crapping out. If you run an aftermarket cam you should definitely consider the use of ZDDP.
 
i know a lot of you here use shell rotella 15w40 but from what i have read, it is mainley for the diesel eng.
shell adv... states that rotella 15w40 meets or exceeds the warranty and service requirments of virtually all diesel and "many" gasoline engines.
so why would you use rotella over an oil made for gasoline engins?
just courious. i use GTX 20w50. jmo.
 
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I use 10-40. No particular brand, since it only stays in the "A" a shrt time, then into the Ford Expedition for the duration. No winter driving...skip.
 
Louis said:
i know a lot of you here use shell rotella 15w40 but from i have read, it is mainley for the diesel eng.
shell adv... states that rotella 15w40 meets or exceeds the warranty and service requirments of virtually all diesel and "many" gasoline engines.
so why would you use rotella over an oil made for gasoline engins?
just courious. i use GTX 20w50. jmo.
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Although many here have and do use Rotella, it is not really suitable for gas engines, the reason being diesel oil contains detergents designed for heavy particulate control. This detergent is in such quantity it can displace any zddp at the point of contact, ie: where the lifter contacts the lobe. Fortunately the original cam and lifters are made from very high quality steel (one of Henry's strong points) and the valve springs are low tension, so the effect is negligible. I would never, ever run rotella with an aftermarket cam, particularly if high performance valve springs are installed.
 
I have been using Dello 15/40 from Costco for 3 years in both my cars. Had the pan off of one and the cam lobes looked fine. My question would be: how many of us use our A's enough to be overly concerned about zinc percentages?
 
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