30w oil
 

was told the other day that one of the fellas was using 30w diesel oil in his car any pros or cons from what i read it has different detergents

Re: 30w oil
 

I use Shell Rotella 30W diesel oil; the previousowner mentioned that the zinc in the oil helps with the babbit bearings.

Re: 30w oil
 

Don't think Rotella has zinc any more. Its a moot point in an A as zinc was not an additive when the Model A was new. Zinc was introduced for the high compression engines of the 50's and 60's

Re: 30w oil
 

30W is fine for summer, I use 10W30 year around.

Re: 30w oil
 

Zinc is a type of extreme pressure additive to prevent/reduce cam lobe/lifter wear in engines with high valve spring pressure. It had nothing to do with Babbitt bearings. Not needed there.

Re: 30w oil
 

Note that the temperatures are in Centigrade (Celsius).

Re: 30w oil
 

Valvoline VR1 racing oil has zinc, get at NAQPA

Re: 30w oil
 

Hey Jynx, if you look for previous posts regarding motor oils you will find enough opinions to keep you busy for days. At the risk of being labeled a heretic I doubt that you could find a motor oil for automobiles that would not be adequate for a Model A.

Re: 30w oil
 

I agree with that. Engine oils in the day were not very good. Even the cheapest oil available today is light years ahead of anything they had back then.
I use what ever oil is on special at the shops - usually 20W50. With a 180F thermostat, the engine temperatures are high enough that it does fine.

Re: 30w oil
 

I use Walmart brand 20-W-50

Re: 30w oil
 

Rotella oil is fine for a Model A

Re: 30w oil
 

I agree with Synchro909. Oils today are so much better than in 1930 that anything would be better. We shouldn't get all wrapped around recommendations from 1930. They were fine for the technology of the day, but we've come a long way in lubrication!

As to viscosity, modern multi-viscosity oils mean you don't have to change oil between summer and winter. The chart posted by katy in post #6 shows the whole picture. I use 20W-50 myself in my old Fords and have never had a problem. 10W-40 would be fine also.

Re: 30w oil
 

Hello.


I am not sure if I have understood the core question correctly.

For vintage cars, a low viscosity can have the disadvantage that the shaft bearings leak leaking oil. Otherwise, a multi-grade oil is always better than a single range.

The most important is the API classification. Because of the non-ferrous metal compatibility. You should not go higher than "SC". Petrol engine oil API SC has anti-corrosion inhibitor, detergent cleaner, HD heavy duty additives. That is enough!

However, the oil still has to be changed many times (max. <1000 miles) because it runs without a filter and only then can the abrasion chips be taken out.

Re: 30w oil
 

From what I have read, not an expert.


One major reason for using multi grade oil is a large portion of wear occurs during motor warm up until the oil/motor is at operating temperature. Straight 30 weight thickens considerably at colder/cooler temps. A multi-grade like 10w30 will thicken to what a straight 10 grade oil thickens to at a cold temperature.


A lot of motors when the temp in late fall/early spring/winter do not warm up all the way unless using a thermostat or if partially blocking the radiator. So the straight weight 30 oil is thicker than ideal all at all times.


Use of a magnetic oil plug can catch quite a bit of the metallic bits that might be floating around in the oil, but if you are especially concerned about this the motor can be converted to an oil filter system. The figure most mentioned here is changing oil every 500 miles. Oil is cheap compared to chances of premature motor wear.

Re: 30w oil
 

The model A engine needs a certain amount of viscosity to cushion the bearings . Ford recommended 20w for winter and 40 w for summer . I use multi grade oil , but figure that a 10w whatever would be too thin to give the necessary viscosity for the older engines when warm . There is more to it than quick flow , in my opinion .

Re: 30w oil
 

used 15-40 the first go, now 10-30 synthetic

Re: 30w oil
 

Good evening!

These motors are unsuitable for low viscosity oils. The large installation tolerances require a thick liquid oil to maintain a hydrodynamic lubricating film in the crankshaft bearings.
In addition, a low-viscosity oil leads to increased oil consumption and the combustion residues in the combustion chamber got too much.

Re: 30w oil
 

My understanding of multi viscosity oil.


10W40 - has the viscosity of a straight 40 weight oil at higher/operating temperatures. Straight 40 weight oil when at low temps is much thicker viscosity, so does not flow/lubricate well.




Multi viscosity oil changes so it has the viscosity of a straight 10 weight oil at very cold temperatures, it is not the viscosity of a 10 weight oil at high temperatures which would be very thin.




So a 10w40 oil attempts to keep the same viscosity for both temperature extremes.

Re: 30w oil
 

You guys got that right! Use what every you want that will get you on the road.

Re: 30w oil
 

Please don't say "10 weight, 30 weight, etc. oil"! That 'W' stands for "Winter", NOT Weight!!