The Stovebolt Site Forums The Shop Area General Truck Talk What Oil for a 1950 235?

Tried to figure it out searching, but it gets confusing as to what the latest thoughts are for the best engine oil in a 50 235ci. I'm thinking 10w-30, but I've also read non-detergent was needed, so I'm just not sure? Sorry if this has been covered a million times before.

Use DELO 15W40 or some other diesel-rated oil year-round. The engine was designed and clearanced for SAE 30 straight weight oil in the summer, and 20W-20 in sub-freezing weather. Water-thin modern oils will make it sound like there's a bunch of little guys with sledgehammers inside trying to pound their way out. DO NOT use non detergent oil in any engine- - - -save it for lubricating door hinges, etc.
Jerry

I'd say stay away from the non-detergent. Sludge happens with it. I use Mobil 1 10-30 but they make at least 6 types of it and that can be confusing.

Do you have an oil filter?

If you have a filter the multigrade detergent oil is better than non-detergent.
10w-30 through 15w-40 seem to used a lot.

If you have no oil filter, it might be a tougher choice. A single grade (30) non-detergent might be the best choice.

Let's see what others think/suggest, and why?

I run SAE 30 Rotella, also a diesel oil, much like was originally specified and good quality.
If I had no filter, or if I knew the engine always had non detergent I'd stick with non detergent.

I'm not sure about the multi weight, have not researched or tried it in my old stuff.. guess I stick closer to original recommendation with the straight weight.

Grigg

Since we have several diesels on the place I buy Delo 15w40 by the case. It goes in most everything including the 51's 216.....in the summer. I change to 10w30 in the winter. I'm likely overthinking things but I do know how viscous 15w40 is when it gets below 30 degrees. This winter (bragging...yes, yes I am) it started @ 18 degrees and I drove it 15 miles to Lit'l Bro's house. It's still 6v and I don't think it'd have started with Delo, it Barely cranked.

Even diesel is dropping zinc from their oil mixes, so you might try to find an additive to dd to whatever oil you decide on.
Zinc dialkyldithiophosphate (ZDDP) is the most common zinc-based additive, and is used primarily as an anti-wear agent to prevent premature engine wear. It also provides corrosion and oxidation protection. However, because the zinc and phosphorus found in ZDDP can negatively affect catalytic converters, it has been phased out of motor oil formulations in recent years. Reducing ZDDP content has drawbacks, as classic car owners have found. Older vehicles with flat-tappet camshafts and, in particular, engines that include high-tension valve springs or other modifications that create high contact pressures can suffer premature wear due to reduced ZDDP levels.

Once a new cam/lifter assembly establishes a wear pattern during the first few minutes of operation, using/adding ZDDP becomes somewhat of a moot point. It doesn't hurt to run it, but whether or not it's essential to prevent wear is debatable.
Jerry

I've noticed that the Delo 400 for my Dodge diesel is sold like this. The same is true for the Rotella T, I think.

Conventional - 15W-40
Synthetic blend - 10W-40
Full synthetic - 5W-40

This tells me that the synthetic is a better lubricant even at lower viscosities. I use the full synthetic, even in the summer. Hope I'm not making a mistake.

Multi-viscosity oils, whether conventional or synthetic or gas or diesel have a higher viscosity index, meaning that they act like a thin oil (the smaller number i.e 5W) when cold and a thick oil (the larger number) when hot, instead of thick when cold and thin when hot as a single viscosity oil would. Synthetics do have a wider range of viscosity than conventional oils. I wouldn't be afraid of running a full synthetic year round, but I'm a cheap bastard and don't want to spend the money on synthetic when I'm going to change it on a regular basis anyway. Some guys run synthetic for longer intervals, but I like to drain the abrasive particles that it picks up on a regular basis rather than let them circulate around the engine.

I like the Rotella CI4,CJ4 because it still has the zinc in it for the flat tappet cams.

Try this little experiment before you put a water-thin oil in a stovebolt engine. Put a pan of oil on the stove, and use a candy thermometer to check the temperature. Tell me how thick it gets when it reaches 250 degrees. Now tell me if you want a liquid the consistency of water trying to take up the clearances between pistons, rods, and other moving parts. The engine is going to hammer itself to death.

Your money- - - - -your choice, but it's very simple to cut through all the bovine scatology that gets posted here with a real-life experiment.
Jerry

So Jerry, since you know the answer to the experiment, why don't you save us the chemistry experiment and tell us all the oils that you recommend rather than telling all of us with an opinion that we are bullsh!t artists. Your opinion here is respected but at the same time a demeaning remark by you is not.

Just try it and you can come to your own conclusions. I already know the answer. People ignore my reccomendations every day.
Jerry

Gentlemen, this subject has been beat to death hundreds of times. Do a search! This particular thread is no longer needed.