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About to own 69 coronet 440….what oil weight?

koosh

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Looking to see which is the proper conventional oil weight for a 440?
Im sure there will be LOTS different suggestions!
 
You are going to get a million opinions. I always just use conventional 10W30 in most of my cruiser/street cars. Whatever is on sale. Never any issues.
No need for synthetics. The seal technology is not o-ringed like today's engines. The old school gaskets will have seepage with synthetic oils.
 
Rick Ehrenberg says 10w30. I worked with a Ford power train engineer back in the 1990s and he said 10w30 was the best "one size fits all" for muscle cars and classic cars.

I've used high mileage 10w30 and a bottle of Rislone zddp. About half of the members here will disagree with this, but it works for me (so far).

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10w30w in cool weather. i'll use 15w40 or straight 30w in hot weather. no real downside to either. i use a lot of rotella. straight 30w rotella still has enough zinc in it. i really think good oil change regimen is probably more important than who's name is on the bottle. modern oils don't have as good of flat tappet cam protection.
 
I run Castrol GTX (they don't make R/T oil) 20W40 non-synthetic oil in the 440 in my 1967 Coronet R/T. I add a bottle of GM EOS (engine oil supplement) at every oil change. This engine has 70,000 miles on it since a rebuild in 1990. Last year, I had the heads off it for the first time since then, and it was clean as a whistle. Burns no oil, but leaks some.
Because of a bad experience I had, I will not use Fram oil filters again. I now use Wix.
 
It's funny everyone has a different favorite house blend, and they're quite happy with how it works..
 
You are going to get a million opinions. I always just use conventional 10W30 in most of my cruiser/street cars. Whatever is on sale. Never any issues.
No need for synthetics. The seal technology is not o-ringed like today's engines. The old school gaskets will have seepage with synthetic oils.
Yeah, here comes the avalanche of personal preferences....
Of course, this one would have been a better candidate for this site's Search box, methinks.
There's been a bazillion threads on this topic already.
 
Rotella or a zinc oil like Gibbs or Lucas hot rod,
10-30, 10-40, 15-40 , that's what I have used over the last few years.
Let's inclued axle bearing preference also to save band width.
Timkin here.
 
I run that Valvoline syn blend "high mileage" 10/30 in everything except my 1.4 turbo.

No gasket or seal leakage issues.

If I can't find that, I've used the motorcraft product that's very similar.
 
I run the valvoline VR1 20w-50. It's not a great cold weather oil but generally I'm driving my car when it's nice and I'm running autocross so lots of sloshing and hard flogging. I ran 10w-30 the first couple times I ran autocross and I'd come back with a lifter tick. So I bumped up the weight and put on a 6qt pan.
 
Here's my suggestion:

Whatever oil you use, with a flat tappet cam you must use oil that has zinc (it doesn't matter if the cam is well broken in, you still need the zinc). If you add your own zinc, don't overdo it - more is not better or your oil turns acidic and causes other problems. You want about 1500 PPM of zinc. My recommendation is to simply buy the classic car oil that has the zinc already in it.

Now to weight. The weight of oil to use depends on the clearances of your crankshaft. New cars, for example, have very tight clearances and therefore use lighter weight oil. Our old cars use heavier oil. So 10W-30, as others have mentioned, is a good place to start. If the car has looser clearances and your oil pressure is lower, then step up to 10W-40.
 
In the old days when we would buy old muscle car Mopars for 300-500 dollars we would start out with 30w. If that didn't have enough oil pressure we would go to 40w. If that didn't have enough oil pressure we would go to Valvoline 50w racing oil. If the motor was so worn out that it still didn't have enough oil pressure we would go to a high volume pump. That never failed to cure it. Even if the bearings were worn down to the copper. So what I'm trying to say is the motor decides what oil you will use. Not you.
 
Rick Ehrenberg says 10w30. I worked with a Ford power train engineer back in the 1990s and he said 10w30 was the best "one size fits all" for muscle cars and classic cars.

I've used high mileage 10w30 and a bottle of Rislone zddp. About half of the members here will disagree with this, but it works for me (so far).

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I use Valvoline 10/30 Conventional with Rislone ZDDP. It has worked for me as well.
 
How about looking at the owner's manual? I was surprised to see 10w30 and 5000 mile intervals for my 65 383! Of course, a modified engine may require different. Have you looked at an owner's manual for your car? Is the engine modded at all?
 
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