Thin High Zinc Motor Oil

[wdills]

Anyone know of a motor oil that is thinner than 10W-30 that already has zinc in it? Yes, I know I can buy anything and add ZDDP, but I wanted something that already had it in there.

[Corvanti]

i use Shell Rotella in the '51. they do have 10W. Valvoline Racing Oil also has ZDDP and i think they have a 10W or 0-20W.

[StudeRich]

Cars Older than the 1980's do not have tight enough Clearances to run 0 or 5Wt. Oil, which is why most Oil Co.'s would not bother making High ZDDP Oils in lighter weight Oil than is needed or safe in these Flat Tappet Engines.

Last I checked North Carolina was not in Northern Alaska!

[DEEPNHOCK]

The racing oils that have higher zinc in them have it because they are 'racing oils'. That's why you see thicker weights (20w50, 40 wt, etc).
The 'racing oil' label gets them around the current laws regarding zinc in oils.
Diesel engine oil has more zinc in it because most diesel engines do not run catalytic converters.
But the diesel oil laws have tightened up, too.

You are better off to buy regular oil at a regular price and add your own zinc supplement.

[rockinhawk]

I think Quaker State DEFY has a 5W 30 or something like that with added zddp for extra protection. Itried it for awhile, but it is a syn-blend and made my cars leak worse. I went back to 10 W30 and STP for the ZDDP content.

[wdills]

The high mileage Quaker State comes in 5W-30 and 5W-20. It says it has more zinc for wear protection, but it doesn't mention being suitable for flat tappet like most of the high zinc oils do. I didn't see any spec sheet that gave zinc content. Anyone know how to find zinc content?

[stude truck 55]

I use Penn grade 1 in my older cars called the green oil ,has higher zinc ,I get mine from the local napa but I know jegs and various other supplier's have it the last I got in the spring I believe was around 5.00 bucks a quart.

https://www.penngrade.com/penngrade-1/

[Commander Eddie]

So, I keep hearing that Studebaker engines don't need added zinc in the oil because the cast iron used by Studebaker for their heads and blocks had a higher zinc content to begin with. So what is the truth here? I use regular 30W oil and have added ZDDP on occasion but not recently. Should I go back to using it?

[StudeRich]

It is not the Heads and Block that are at risk to wear, it is the Camshaft and Lifters. So the two are not related at all.
But many people here have said there is no truth to the Urban Legend about the High NICKLE content and others say there IS.

[Commander Eddie]

It is not the Heads and Block that are at risk to wear, it is the Camshaft and Lifters. So the two are not related at all.
But many people here have said there is no truth to the Urban Legend about the High NICKLE content and others say there IS.

Thanks StudeRich. I guess I'll just have to remain confused. And thanks for the clarification on which metal and what parts are involved.

[PackardV8]

So, I keep hearing that Studebaker engines don't need added zinc in the oil because the cast iron used by Studebaker for their heads and blocks had a higher zinc content to begin with. So what is the truth here?

No, there's absolutely nothing special about the cast iron used in Studebaker heads and blocks. It machines just like an other. No cast iron of which I'm aware uses zinc as an alloy additive.

No, a sub-set of the Stude community is the same as those in the Hudson, Auburn, Buick, et al, who've brought in engines and asked how much extra we're going to charge them to machine their "high-nickel" parts. It's difficult not to allow them to pay more, but someone, somewhere will eventually tell them it's no different.

jack vines

[wdills]

I found Royal Purple HPS has the needed zinc content and is available as 5W-30 and 5W-20. I am going to try the 5W-30 on my upcoming oil change and see how my oil pressure does.

[StudeRich]

Maybe check your Rod Bearings in 10,000 Miles, and see if ANYTHING is left!

[Bud]

I don't see any reason not to use a thinner oil such as a 5W-30 or 10W-30 in a Studebaker engine that is not in its last stage of life. The bearing clearances in the 5.3 engine in my 2010 Chevy Silverado are no different than what is called for in a Studebaker engine and it has run just fine with good oil pressure and no consumption and all it has had is either Pennzoil or Mobil 1 synthetic 5W-30. A 5W-30 oil is an SAE 30 oil when warm, it just flows better than an SAE 30 or something like a 20W-50 when it's cold which to me is a good thing. I recently bought a couple of jugs of Chevron Delo 400 5W-40 synthetic that will go into both my 62 GT and the 63 Avanti at their next oil change. A good friend has been using it in his 52 Packard with good results. He says it cranks faster with the 5W-40 in the pan over 15w-40 or straight 30. He says the oil pressure is good and there is no difference in consumption. Time marches on, I say to take advantage of the changing technology especially when it comes to lubricants. Bud

[wdills]

I have discussed the switch with Jack Vines and he has endorsed the change.