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

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AyWoSch Motors

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So I have a new crate 350 long block, that I'm putting in my 86 K15 soon.
I want to build it with all new parts, and have the best of the best, I want this engine to last forever. Now its nothing crazy, just a stock spec 350 small block. I'm not gonna hot rod it, just leave it stock.
But I'm curious, what would the best possible oil I could use to ensure maximum protection, lubrication, longevity, etc?
What weight oil number one. I mean, I use 10w30 in everything I own, but is there something better?
Also, should I use classic style oil, or a full synthetic?
What brand would be best? Mobile 1, valvoline, I don't know.
And what about any additives?
"Extra protection", Lucas oil, AMS oil...
Also, a good friend of mine swears by adding extra Zinc to the oil. Old or new, he adds zinc to it. Anyone ever hear if that?

Where I live it it rarely gets below 0° or above 90°. High altitude, 7000 feet, if that makes a difference.
This truck is a half ton, short bed, manual trans, it's my almost muscle truck. It runs cool It's never going to haul any crazy loads or go to far. The occasional car hauler, or load of dirt.
It will most likey only go to town and back to go to work, and run about, about a 30mile round trip. Possibly a trip to Santa Fe now and then, a 120 mile round trip.
I do like to show off around the buds now and then, or drag race between the lights when no one is around, so the occasional high rev foot to the floor moment, but that's it.

What would you all suggest, for the absolute best oil possible?
 

Curt

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After my own bit of research,I use Valvoline conventional.I don’t use synthetic.As far as additives,people swear by Lucas.

I had a very expensive gm crate engine and ran synthetic,after first 2 oil changes.Eventually my front main started to leak.(less than 5k miles)

Different crate engine from same place,running conventional,no problems,5x the mileage.Might not be much of a test,but good enough for me.

I’ve heard it said that some synthetic oil is too good,too slippery.Not sure.I watch a engine builder on YouTube and this issue was addressed.Deboss garage.His theory and observations was interesting.Might give it a look.

Ultimately,I recommend conventional oil,3k oil changes and a quality filter.I personally use wix or ac delco and Napa gold.

There’s another fella (project farm) on YouTube that tested out air and oil filters.His tests was good enough for me to take every single K&N air filter out x3 vehicles.

Anyhow,I believe there’s been quite a few technological breakthroughs on oil and filters,but I also believe some of it could be snake oil in certain applications.

My 2 cents
 

Curt

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Oh,I use 10-30 in winter,10-40 in summer.
 

wanderinthru

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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.
 

AuroraGirl

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I would use a break in oil from a reputable manufacturer because the nature of break ins and follow the instructions for seating rings etc etc

Once in the normal period, depends.
Roller cam? EFI? Temperature when used? Daily driver? '
If its not roller, zinc additive or zinc oil, if its efi and daily in a decent climate, long mileage on the oil, but drop mileage for carburetion, extreme weather, sits/traffic miles.
use a nice large AC Delco or WIX or KN or other premium filter.

Do spec your oil for the right temp @wanderinthru youre in one of the dakotas, arent you? You need some 5w-30/10w-30 or even better, 0w-30 in the cold part of the year and 10w-30 in the warm(I do this, depends on your interval)
the first number isnt for when the engine is running
SAE 30 doesnt move very well( and not really at all) in an engine thats -30. It has to be warmed up by the oil pump trying to pull it through the pickup and the engine rotating in it for an uncomfortable amount of time before the rest of your engine is able to be oiled(top end yikes!). hydraulic lifters wouldnt like that too much... the cam lobes on flat tappet not so much either.

Also harder to start.
 

Salty Crusty

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I use a 50/50 blend. And like Curt, I use Lucas products.
The notion that synthetics are "too slick" has been disproven many times.
Today's oils, even conventional, are light years ahead of 30 - 40 years ago. Most have very good additive packages and will be fine.
Just make sure to change it regularly.
And toss the break-in oil after 100 miles, it'll be dirty.

Best things you can do while the block is at the machine shop is to have it torque plate honed, then plateau honed. Plateau honing knocks off all the microscopic peaks left by honing stones and makes 'em flat-topped, like a plateau. This cuts down break-in time significantly. While you're at it, have the block decked square. I have mine cut to leave the piston .005 in the hole.
I have one I built about 15 years ago that now has 125K miles or so on it. With flat top 4 valve relief pistons, I'm at 10.1:1 with vortec heads and an LT-4 stock cam. Oil looks brand new at 1000 miles thanks to how well the rings seal, particularly at TDC where the torque plate honing job really shines.
 

Memaloose

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I always use what the manufacturer recomends. I don't use additives and I don't go over 3,000 miles on an oil/filter change. The most important thing is regular maintenance. Check your fluids regularly and change them regularly whether it's brake fluid, p/s fluid, tranny fluid or engine oil. Look in the owners manual and use it for a guide.
In my original 1975 350 with 85,000 miles, I use 10/30 year round and a Wix or Napa Gold filter. I'm not opposed to a straight 30wt here in AZ.
The engine uses no oil and there are no leaks. I buy what's on sale on the oil. All the oil companies use the most advanced formulas so I don't worry about additives.
 

Shorty81

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I use Schaeffer in my flat tappet engines.
 

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SquareRoot

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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.
 

AyWoSch Motors

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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.
I thought I had added that, sorry.
It's a standard style flat tappet cam with standard hydraulic lifters.
 

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