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What oil ?

I've done a lot of research on this topic, but I'm in now way an expert. Our old style flat tapped cams and lifters need zddp. Our stockish or mild engines are OK with 1000 to 1200 ppm zinc. The more the cam lift with stronger valve springs and other mods, the zinc ppm should go up. Recent oil analysis show that Shell Rotella T dino oil still has about 1200 ppm zinc, synthetic closer to 1400 ppm. Most all of the heavy duty engine oils (aka dino diesel oil) have about 1100 to 1200 ppm zinc. I run a 518 lift cam in my 383. I run 15W40 Shell Rotella T dino oil with a bottle of STP. I like heavy engine oil for the summer because I do a lot of highway driving. With my low gears I'm turning 3000 to 3500 RPM down the road. STP has a large amount of zinc. I broke my cam in with Shell Rotella/STP.

BTW, standard oil like 0W20, 10W30 and such, the kind with the round "star" on the label, have virtually no zinc, or none at all.
 
if i am using my car in fall/spring/summer...and winter start ups (not leaving garage) is 20-50 okay for year round?
 
In NJ, I imagine the spring/fall mornings/days can sometime get a little cold. 20w50 when cold is like molasses. Maybe a 10w40 would be better under those circumstances.
 
Double post.
 
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if i am using my car in fall/spring/summer...and winter start ups (not leaving garage) is 20-50 okay for year round?
If your car is garaged then I guess it would be OK, if the garage is warm enough. That way when you start it up the oil isn't thicker than snot. There's always the option to use a lighter standard oil with a healthy dose of zinc additive for the winter. Shell Rotella synthetic is thinner with a good amount of zinc that you could run in the winter.
 
If your car is garaged then I guess it would be OK, if the garage is warm enough. That way when you start it up the oil isn't thicker than snot. There's always the option to use a lighter standard oil with a healthy dose of zinc additive for the winter. Shell Rotella synthetic is thinner with a good amount of zinc that you could run in the winter.
If it were straight 50 wt, then it would act thicker than snot. That's what the 20 does.....it acts thin when cold.
 
If it were straight 50 wt, then it would act thicker than snot. That's what the 20 does.....it acts thin when cold.
Not for me. I tried 20W50 "once". Too think on cold mornings in my cold garage. Engine made some funny knocking sounds when I went to start it up. After about 15 seconds it would finally go away. I didn't like that. On warmer days it didn't do that on a cold start. Went back to 15W40 which didn't make any funny sounds cold, warm or hot days. So, 20W50 can be too heavy for some under certain circumstances...
 
analysis show that Shell Rotella T dino oil still has about 1200 ppm zinc, synthetic closer to 1400 ppm. Most all of the heavy duty engine oils (aka dino diesel oil) have about 1100 to 1200 ppm zinc. I run a 518 lift cam in my 383. I run 15W40 Shell Rotella T dino oil with a bottle of STP. I like heavy engine oil for the summer because I do a lot of highway driving. With my low gears I'm turning 3000 to 3500 RPM down the road. STP has a large amount of zinc. I broke my cam in with Shell Rotella/STP.

That's true on the diesel oils up till recently. Alot of those have been dropping in the zinc level as well, and from what I've read, the EPA has been pushing lower levels in those oils also. I'm just sayin, to keep an eye on it.
 
That's true on the diesel oils up till recently. Alot of those have been dropping in the zinc level as well, and from what I've read, the EPA has been pushing lower levels in those oils also. I'm just sayin, to keep an eye on it.

does that have to do with the republik of kalifornia low-sulfur law?
 
does that have to do with the republik of kalifornia low-sulfur law?

Probably and it also increased the cost of medium duty trucks about 3/4K to meet 2012 emission standards nationwide.
 
Just a note guys, I wouldn't be running oil weights not recommended chrysler. Coming from an engineer (me), journal bearings are designed for specific oil weights to prevent wear. The size of the journal and bearing materials dictate the oil weights and are extensively tested by the manufacturer. Switching to a heavier weight oil gains you nothing typically unless your engine is heavily modified. In fact using a heavier oil then necessary can rob horsepower and actually increase wear.

Not telling you guys what to do, you all know your own engines, just wanted to throw this out there so guys with a stock engine don't think they should be running 20w-50.
 
So then... Whats best for a high mileage stock engine?
318 in my case. Really wet and mostly cold NW weather. Not garaged.
 
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