Anyone using Castrol

[60eldo]

 Is anyone using Castrol GTX Classic 20W 50. Aparently it has zinc. After my rebuild my guy said to always use Valvoline VR1, but after some research, I read that it should not be used in a daily driver,,,any thoughts

[Lexi]

Never heard that before. How did they qualify that? Clay/Lexi

[Moody]

Was he talking about using the VR1 for break in?
I used to used Castrol, but switched to Mobil 1. Long story. 
My dad always bought cheap oil, and never had an oil related issue with any of his cars.
Oil threads are never conclusive.

[gkhashem]

In the description for VR1 it states it is formulated for classic cars too. So not sure why you cannot use it?

[Big Fins]

Let's see, we have how many forum members? 

This thread will go on forever on what brand, what weight, what color the oil should be. It'll be fun anyway.

Mobil Delvac 15W-40 for me in all the Cadillac's over the years. Good weight for the heat down here and plenty of ZDDP.

[The Tassie Devil(le)]

Zinc is really important.

Without it, your Lifters and Cam Lobes will end up like these pictured.

Plus, all the missing micro pieces of metal that is missing will have been distributed throuought the internals of the engine.

I am just rebuilding two engines with a friend who had this happen.

Bruce.

[Cadman-iac]

Mobil Delvac 15W-40 for me in all the Cadillac's over the years. Good weight for the heat down here and plenty of ZDDP.

  Is Delvac what replaced what was called Delo 400?
 I used to use that back in the 80's when I lived close to a Chevron warehouse.

  Rick

[Jeff Rosansky CLC #28373]

What's the verdict on zinc with catalytic converters, such as on a 79?

[Clewisiii]

I guess I am being a snob using AMSOil.

I used 30 weight royal purple for the Cam break in. I have Amsoil 30 weight breakin oil in it now for the next 500 miles. Then switching to Amsoil 10w30 high zinc for regular use.

[Big Fins]

Is Delvac what replaced what was called Delo 400?
 I used to use that back in the 80's when I lived close to a Chevron warehouse.

  Rick

No. Delo 400 is a Chevron product. Delvac is produced by Mobil Oil Corp. I only use it because it was free. When I would get the oil changed in my Peterbilt, I always added a gallon of Lucas Oil Stabilizer and the shop would then fill the gallon jug for top offs between changes.

My truck never burned or lost an ounce of oil between the 10,000 mile services and I built up a good stock of about 20 gallons. It also makes for a good engine flush on the daily drivers. I drain the oil and filter, reinstall the filter, fill it up and drive about 50 miles. Then I drain out the other and put in the proper oil for the twin turbo engines. The insides are still like brand new on those vehicles.

What's the verdict on zinc with catalytic converters, such as on a 79?

If you don't burn oil, there should be nothing to bother the converter, though it is said it can plug them up. I have the converter removed from my car. It was rotted and plugged, so I have a section of pipe replacing it. The Greenies don't like Florida because we don't have emissions inspection here. We get too many hurricanes that keep the air clean.

[bctexas]

Lake Speed Jr. (you may recognize the name from his father's racing career) is a tribologist who specializes in automotive applications.  He has produced a series of YouTube videos (as "The Motor Oil Geek") that cut through the marketing and internet hype get to the science of engine lubrication.  Here is one about ZDDP:

https://www.youtube.com/watch?v=erxjPicpYyw

and another about oil and fuel additives:

https://www.youtube.com/watch?v=CAGT5inQScE

He is a Certified Lubrication Specialist and Oil Analyst, and his conclusions are based on science, laboratory testing and experience. 

Happy Motoring!