Best oil? Type, brand, viscosity, additives, etc.

[Camar068]

I like Amsoil Z-Rod 10W30 for my flat tapped lifter engines.

compare Amsoil to Amazon.....might change your mind. Yes Amazon is lower here and there (#'s wise).....but higher than some of the name brands sold in local stores. To really understand the difference, you have to read up a bit on the science of each ingredient. Been a while, don't ask me. But I did the comparison a few years ago and was happy with the choice.

Petrolium Quality

 

[rpcraft]

Best oil discussions are like asking about the best tire or putting nitrogen in your tires. Find a good quality brand that is affordable. I like synthetics and usually stick with Rotella because it's affordable and available most anywhere. I'm running an LS swap so I use whatever is according to the oem engine spec (5-30 if i recall correctly). As far as power steering and brakes, I usually buy whatever I see first for the larger container when in the auto parts store and as far as transmission fluid goes again, whatever the proper type is at the lowest price. Same for gear oil. I use Fram filters as well as Mobile, mostly because they are affordable, and plentiful, and functional.

 

[WFO]

I just ordered this for my 69 SS396 Chevelle.

Castrol GTX Classic 20W-50 Conventional Motor Oil, 1 Quart (Pack of 6)​

About this item​

• Castrol Classic 20W-50 is suitable for use in automotive gasoline engines where the manufacturer recommends an API SJ or earlier specification 20W-50 lubricant. NOTE: NOT FOR USE IN MODERN ENGINES WITH CATALYTIC CONVERTERS OR WET CLUTCH APPLICATIONS
• Specialized additives containing high Zinc and Phosphorus for extreme wear protection
• Formulated to maintain tough and thick oil film even under severe conditions
• Minimal foaming and high resistance to thermal degradation
• Compatible with gasoline and alcohol-based fuels

Amazon.com

 

[squareton]

This is my experience with semi engines, they will wear to what oil you use. If you start with a certain oil stick with it, different oils create different wear patterns. My cams in my isx were replaced last year at a cost of 14k but that included new bearings. Interesting note that the bearings that came out looked normal in wear even though the oil type wasnt kept consistent. I know this because I bought it from my dad and I was the original driver in this truck at 550k miles. The cams went at 1million 200k miles and its still humming away, obviously cam wear appears more than bearing wear at least in this engine.

 

[Grit dog]

@AyWoSch Motors , if you’re after the bestest best, by all means buy the most expensive stuff. It will work great and likely maybe who knows, make it last longer.
That said, you don’t appear to be the high roller, $15-20/qt oil kind of guy, but rather much more practical of a person.
With practicality in mind, any quality oil with proper maintenance intervals will be just fine imo. For a long time to come.

Personal opinion, I run 15W40 or 5W40 in virtually every 4 stroke engine we have. And have for years. The number of exceptions are small and specific.
From our 6.4 Hemi to 450 race bike, to 350 Chevy boat engine to of course diesel trucks, and everything else that needs an oil change.
That would be my recommendation

 

[Bextreme04]

Personally, I still run straight 30 weight. Never bought into the multi vis deal, 10/30 is 10 weight and oil gets thinner with heat period. Buy mine in a 5 gallon bucket, half the price of quarts, believe it's Mobile, but would have to go look. All my research shows that these engines are still made with the same clearances they started with, and designed for 30 weight oil when new. Oil is a "cushion" as well. Also like the Lucas and add a half quart at a change. Quality filter, I use Wix, because thats what the parts store sells. A fwiw, Car Quest filters are now made by Fram, thats the reason the local store sells Wix. I change mine when it needs a quart, usually around 5000 miles ( 5000 miles is what GM called for back in the day)
For a new engine "they" do say zinc is important, there was a thread here someone did a while back that is very informative. Think it was SirRoybin. On a new engine I would change it very often to begin with, say a 100, 500 then 1000 miles then just put it on the schedule you choose.
Just my opinions, an old hard headed pragmatic SOB, so there you go. Good luck.

This is just flat out not true. 10w-30 is not "10 weight oil". 10w-30 is a 30 weight oil that has additives in it to prevent it from thickening as much at cold temperature. A 10w-30 and a straight 30 weight will have the same viscosity at 100 degrees C, because that is how the oil gets graded. If they had different viscosities at that temperature(which is right in the middle of most engines standard oil operating temp), they would not both be -30. The "10W" at the front means that the oil will have the same viscosity at cold temperatures as a SAE 10 oil would at that temp. This is still thicker than either of the oils at "operating temp". If you look at the graph below, you can see how the 30 and 40 weight oils, whether they are straight grade or multi-viscocity all converge to almost the same viscocity at operating temps. They vary widely at cold start temps though. Once you get to freezing temps, the SAE 30 has double the viscocity of the 10w-30.

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If you zoom in on the top end of the graph, you can see that the SAE 30 and 10w-30 have the exact same viscocity at normal operating temps.

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If you live anywhere that gets below freezing, I would HIGHLY recommend you switch to the appropriate oil for the ambient temperatures to prevent oil starvation and pump wear during cold starts.

 

[Paladin]

I cant believe this thread has survived this far without anyone asking the OP if the cam in his "new" engine is roller or flat tappet. Use the wrong oil with flat tappets and it will be an "old" engine before break-in is done.

And I can't believe there is another thread asking this very same thing that has been ask umpteen thousand times before. Geez Louise!!!

 

[AuroraGirl]

@AyWoSch Motors , if you’re after the bestest best, by all means buy the most expensive stuff. It will work great and likely maybe who knows, make it last longer.
That said, you don’t appear to be the high roller, $15-20/qt oil kind of guy, but rather much more practical of a person.
With practicality in mind, any quality oil with proper maintenance intervals will be just fine imo. For a long time to come.

Personal opinion, I run 15W40 or 5W40 in virtually every 4 stroke engine we have. And have for years. The number of exceptions are small and specific.
From our 6.4 Hemi to 450 race bike, to 350 Chevy boat engine to of course diesel trucks, and everything else that needs an oil change.
That would be my recommendation

does this also extend to cold conditions

also I realized the other day how much local shelves do NOT Carry 0w-40 or even many 0w-30s

 

[Bextreme04]

does this also extend to cold conditions

also I realized the other day how much local shelves do NOT Carry 0w-40 or even many 0w-30s

We don't really have the kind of cold here in the Pacific Northwest that you are worried about in Wisconsin. I run 5w-30 synthetic in my 2011 suburban year round. Its got heavy duty cooling and engine/trans oil coolers with thermostatic valves, so they stay pretty much the same temps year round. We rarely are below freezing here and the summer highs are in the 70's-90's, so the 5w synthetic is adequate in both winter and summer.

The 1980 is currently running 10w-30 Castrol conventional until it gets through the first 5,000 miles on the new engine. Then it will also go to the Mobil 1 synthetic 5w-30 so that I have the same oil in everything. Its freshly rebuilt with modern gaskets and I know the tolerances on the bearings are good for 5w-30. My Gen VI 454 that will eventually go into it also calls for 5w-30 from the factory and that thing had 288,000 miles on it and still drove great when I bought it. It was a Montana truck originally.

 

[SquareRoot]

And I can't believe there is another thread asking this very same thing that has been ask umpteen thousand times before. Geez Louise!!!

Waiting for the follow-up question regarding how to improve gas mileage.

 

[SirRobyn0]

You might want to check out this this thread if you haven't see it already. https://www.gmsquarebody.com/threads/zinc-engine-oil-and-flat-cams.34404/

I've heard a lot of opinions, but went out and did what research one can from a keyboard.

What I'm going to say on the zinc thing, is assuming your running a flat tappet cam you need high zinc during break in, assuming it is a stock or mild build once you have broken it in, and you can keep up with this high zinc for a few thousand miles or more, but the thing of it is, to much zinc can build up in a engine over time. High zinc oils are lower detergent than modern oils. Remember we use to have trouble with engines slugging up, today it's very rare. So you'd be best to use a high zinc oil and / or additive for the break in, after that switch to the flavor of your choice of modern oil. I've seen guys run full syn, in these motors, but obviously any good quality off the shelf motor oil of the correct viscosity will be just fine.

Look at the back of the oil bottles on the shelf valvoline high zinc racing oil carries no SAE certifications, (nor do the other racing oil brands BTW) and says 3K oil changes or less. Any even cheap modern oil is rated for longer than 3K now. I'm not saying high zinc oil is bad I just want to point out there is a trade off as some folks seem to think it's the bee knees. If your running a high lift cam and or stiff springs then high zinc is a requirement for life and you just have to live with the down falls.

 

[AuroraGirl]

You might want to check out this this thread if you haven't see it already. https://www.gmsquarebody.com/threads/zinc-engine-oil-and-flat-cams.34404/

I've heard a lot of opinions, but went out and did what research one can from a keyboard.

What I'm going to say on the zinc thing, is assuming your running a flat tappet cam you need high zinc during break in, assuming it is a stock or mild build once you have broken it in, and you can keep up with this high zinc for a few thousand miles or more, but the thing of it is, to much zinc can build up in a engine over time. High zinc oils are lower detergent than modern oils. Remember we use to have trouble with engines slugging up, today it's very rare. So you'd be best to use a high zinc oil and / or additive for the break in, after that switch to the flavor of your choice of modern oil. I've seen guys run full syn, in these motors, but obviously any good quality off the shelf motor oil of the correct viscosity will be just fine.

Look at the back of the oil bottles on the shelf valvoline high zinc racing oil carries no SAE certifications, (nor do the other racing oil brands BTW) and says 3K oil changes or less. Any even cheap modern oil is rated for longer than 3K now. I'm not saying high zinc oil is bad I just want to point out there is a trade off as some folks seem to think it's the bee knees. If your running a high lift cam and or stiff springs then high zinc is a requirement for life and you just have to live with the down falls.

very rare except in POS engines or complete disregard by owner for oil changes* lol.

Im thinking of a lot of engines made by GM from mid 2000s to 2010s where a certain label named ecotec was applied to them

 

[SirRobyn0]

very rare except in POS engines or complete disregard by owner for oil changes* lol.

Im thinking of a lot of engines made by GM from mid 2000s to 2010s where a certain label named ecotec was applied to them

Right and ecotec motors that tended to do that was an oiling system design flaw, and even then not all of them slugged up.

What I'm talking about. It gets worse the farther back you go, but pre-90 for sure. I remember even in the 80's my Dad was religious about his 3K oil changes and had some minor issues with sluge in his 350, and IH-345, but here my 305 is clean as a whistle inside. My 305 with 200K is still going, his 350 was getting tired after 100K, a lot of that. The longevity in engines as in general is thanks to improvements in oil detergents. We'd loose out on those improved detergents if we switched to high zinc engine oil.

 

[AyWoSch Motors]

And I can't believe there is another thread asking this very same thing that has been ask umpteen thousand times before. Geez Louise!!!

Whoops, sorry. I looked, didnt see another one.

 

[AyWoSch Motors]

Waiting for the follow-up question regarding how to improve gas mileage.

Nah, I'm not worried about that. Its 35 years old, has a V8, and is shaped like a brick, and I have a lead foot, so an improvement in has milage for me is called not driving it.