The Stovebolt Site Forums The Shop Area General Truck Talk Oil weight inMissouri

I moved to Missouri from California and my 1953 GMC with a 55 Chevy 235 engine needs an oil change. What weight oil should I use? I believe the last oil was 5-30 weight before it was stored. The truck is garaged If that has any impact.

What part of Missouri did you move to? Check out the Heartland threads to see what may be going on.

Myself, I run Rotella 15-40 in everything except the engines that require synthetic.
Being that it is garaged, I would think 5-30 would be a little thin for a engines of those years.

Hopefully HRL will give us his thoughts!
Don

I've been expressing my opinion on oil weights for years, and I'm getting ignored, ridiculed, and accused of being an ignorant liar. It's somebody else's turn on the bullseye. I use Traveler brand 15W-40 that I buy from Tractor Supply Co. in 5-gallon pails in every 4-atroke engine on the place- - - -tractors, cars, trucks, lawn mowers, generators, a Harley Soft Tail, and a pressure washer. No oil-related failures in the 30-something years I've been doing that!
Jerry

I use Mobil Delvac 15W-40 in both my old cars. 5 weight is too thin IMHO. A lot of folks like 10W-30 and have good luck with it but I feel it's still a tad too thin. Any 15W-40 that meets current spec will do just fine. You don't need to pay the Rotella price. The Delvac is 50-60% the price of Rotella.

I run 15W40 Walmart diesel oil summers in my '51, at the winter change I do with Walmart 10W30.

For decades I used Delo 15W40 in our diesel trucks. Then I switched to Walmart Tech 15W40 (dino) oil a few years ago. In every oil comparison I've seen it ranks near the top in all categories that count. My Old Dodge Cummins diesel is at 300k and no engine problems. One nice benefit of the 15w40 is the higher viscosity quietens down the '51 3600.

In reading theses posts I take that diesel oil is good for gas engines like in a 235.My local Canadian tire has a 5 gallon pail on sale this week

I've never seen a diesel oil that didn't have an API "S" (Spark) designation as well as a "C" (compression) designation on it.

So is this what most use

Well, I just checked out Shell Rotell T4 and it doesn't list SN classification which is for gasoline engines. But I wouldn't be afraid to use it in a gas engine. Diesel oils are much heavier duty than gasoline only rated oils in general.

Mobil Delvac spec. https://www.mobil.com/en/lubricants...products/mobil-delvac-1300-super-15w-40/

Another Diesel/gasoline oil to consider is Walmart's SuperTech. I have never used it, but it meets both Diesel and gasoline specs, and is cheaper than the name brand stuff. Probably equivalent to Tractor Supply's offering.

Thanks for all the good information. My engine was rebuilt a couple years ago and only has around 500 miles on it. Should I still use 15w40 during the winter months or would a 10w30 be better? Is there a huge difference?

I think you'd be OK either way. I use 15W40 year around. With either you need to let the vehicle run for a few minutes before driving it, especially in colder weather.

[' What weight oil should I use?"

Good morning Buck.

Is there some reason you don't ask this question of a lubrication engineer at one of the major oil companies? Since their companies sell a full range of lubrication products they have no reason to steer you to anything other than the product best suited for your application.

I have found them to be very knowledgeable and helpful, Here's just one example of many. My street rod roadster has a Chevy Vega steering box and the recommended lubricant for that, a very low viscosity self leveling grease, has been unavailable from GM for nearly 20 years. I called Shell Oil and the lubrication engineer who took my call took the specifications of the product I needed and he cross referenced it to a Shell identical equivalent of that product. Because I was looking for an amount smaller than anything Shell sells he sent me a complimentary container of it as a "sample".

It seems miraculous to get both a product known to be the exact right one for the application and to get it at no cost, but that actually resulted from a simple phone call asking for information. I've had identical experiences when other lubrication questions came up. I'll take professional knowledge over amateur anecdotal opinions any time.

Here's a current discussion of a very similar topic on the Chevytalk forum.

https://www.chevytalk.org/fusionbb/showtopic.php?tid/362566/post/new/#NEW

Notice the graph and links to additional information posted by the Moderator "Grumpyvette" To those of us who like seeing the data with our own eyes that kind of complete information is really appreciated.

Ray W

You're in Southern California. No need to change weights at all. I'd wager $100 that you've rarely seen below freezing. If you were in Alaska, then maybe, but I run 15W-40 in my diesel year round up here.
[on edit] Went back and saw that you're in Missouri now (you should change your profile location.) You'll still be fine with 15W40 year round. It might occaisionally get colder there than in SouthCentral Alaska, but still OK.

What does the manual say?
For my 58 it's 10w-30 except for extreme hot or cold.

I took the suggestion by Yar and called the Shell Oil Lubrication Engineer and he cleared up the question of which motor oil is best in older engines. He said that older engines need Zinc and he suggested to use Rotella T4 15W-40 diesel motor oil as it contains 150% more zinc than motor oil for gasoline engines.

I've noticed that the Delo 400 oil for my D*dge diesel is:

15W-40 for conventional oil
10W-40 for synthetic blend
5W-40 for full synthetic

It's the same for Rotella, I think. Does that mean that the synthetics are better lubricating at lower temps so they can go less viscous?

Warren Performance (just down the street) bottles most of the store brand oils sold in the US. This includes Walmart, Costco, TSC Traveler, All Fleet, Amazon, Peak, Mag 1 and many others. I've been told that Walmart Super Tech is the same stuff as Mag 1 (all good stuff).

John

After 50+ years of messing around with cars, I have come to the conclusion that motor oil is motor oil...

The cheapest oil you can buy today is better than anything available in the 1950s. As for the recommended viscosity or weight, this is what the 1955 Owners Manual reads:
http://chevy.oldcarmanualproject.com/chevyowner/55om17.htm
Given that I would say any 5W30 or 10W30 would be plenty adequate for year round service in Missouri, or anywhere in the lower 48.

"Warren Performance (just down the street) bottles most of the store brand oils sold in the US. This includes Walmart, Costco, TSC Traveler, All Fleet, Amazon, Peak, Mag 1 and many others."

John,

Doesn't Warren Distribution make Mag 1 motor oil? If that is so aren't all the oils you listed the same products in different packages?

"After 50+ years of messing around with cars, I have come to the conclusion that motor oil is motor oil..."

Frank,

Are you saying that they all have the same additive package and quality or only that they all fit the broad category of "oil"? What is the science behind the statement?

According to buckaroo01 he learned from a lubrication engineer that there are differences:

"I took the suggestion by Yar and called the Shell Oil Lubrication Engineer and he cleared up the question of which motor oil is best in older engines. He said that older engines need Zinc and he suggested to use Rotella T4 15W-40 diesel motor oil as it contains 150% more zinc than motor oil for gasoline engines."

Over the decades I've seen many automotive publications that say the same things that the lubrication engineer told buckaroo01 and provide the details of the differences.

Ray W

My statement was too general, but applicable I think, to our old trucks from the 40s – 50s, especially when combined with my statement that followed, “The cheapest oil you can buy today is better than anything available in the 1950s.”

Warren Performance MAY tweak the additive package for the different brands they supply, and they would definitely be different based on whether they're Diesel CK-4 or Gasser SN API spec.
Quite a few of the big companies, Chevron, Mobil, etc. have info on their websites with the additive values for the various oils. For example, here's the Product Data sheet for DELO 400.

That's correct. Warren has various additives for whichever product they are bottling. I believe there's quite a bit of monitoring and testing involved to assure the proper blends. An insider told me that Mag 1 and Walmart's SuperTech are the same exact recipe. I've also been told that they bottle for BP (British Petroleum) at one of their other plants. I would like to think that if BP were allowing them mix and bottle their products they must know their stuff.

John

Frank and John,

Isn't one of the things that has affected motor oil formulations emissions requirements. For example I thought I read somewhere that diesels are now equipped with cats and the old oil formulations damaged the cats so a new diesel motor oil formulation was required. If that is so maybe the older oils are actually better for gas engines with flat tappet camshafts. That's an interesting question to me because I'm no expert on the subject, just an interested amateur.

Ray W

In about 2005 I switched from 20/50 Valvoline to DELO 15/40 because I had a more or less unlimited supply from draining the residual after a delivery from the tankers I was driving. Eventually, I used the last of what I saved only to discover that Chevron had greatly reduced the metals in the additive package after diesels got trap oxidizers etc. So I began using an after-market additive at $15 a pint in addition to the DELO I got from COSTCO. I had been using DELO in my flat-tappet motorcycles too. So it's gotten expensive.

Motorcycle-specific oil from NAPA is about the same price as DELO with an additive. I'm pretty careful about oil for my Norton Commando as the tappets don't even rotate and I had two cams go flat on that engine. The last replacement was a work-hardened used one and I've had no trouble since. On my Mercedes diesel, the rockers ride directly on the cam so there's nothing to rotate and I've used the expensive additive package on that too. After 10-15 thousand miles the cam still looks good when I pull the valve cover to adjust the valves. So all appears to be well.

Lately I discovered that Valvoline Racing Oil has the metal additive package and is less expensive than, say Harley-branded oil and besides don't Harleys have roller tappets now too? So, I've been putting Valvoline Racing Oil in my 235 the past couple of changes.

Anyhow, it's good news that Rotella T4 15/40 has the zinc additive. Is it more expensive than DELO? I wonder if it would be OK in the Mercedes diesel.

I think the change in diesel oils was when the spec changed from CJ-4 to CK-4. It did reduce the ZDDP additive components by about half. Not sure the reasoning behind it but it wasn't for catalytic converters, as the light duty diesels had those since around 1999. It was probably due to the diesel particulate filters in the exhaust than need diesel exhaust fluid (urea) for operation.

One brand I haven't seen mentioned in this thread was the Lucas Oil - "Hot Rod & Classic" branded oils. Supposedly made specifically for these older engines that need the higher level of Zinc and other additives... although much pricier at $35-40 per gallon.

I appreciate the information you guys are bringing forward. There is a lot to know on this subject.

These articles from Hot Rod are interesting reads on the subjects of modern oil's effect on engine and flat tappet camshaft component longevity:

https://www.hotrod.com/articles/0803sr-modern-engine-oil/

https://www.hotrod.com/articles/hrdp-0702-pitstop-zinc-oil-additive/

Ray W