Castrol GTX Classic 20-50 Motor oil with High ZDDP levels

[desoto1939]

I know there has been a-lot of questions and answers about the use and requirement of replacing the ZDDP properties for our older cars.

Castrol is now offering a  motor oil called Castrol GTX classic W20/50 that has one of highest ZDDP amounts.

 

I contacted Castrol and they provided me with a tech sheet about the oil. I also have another document with info on ZDD properties written by Egge Machine company.

 

I have attached both documents for your reading.

 

Rich Hartung

Desoto1939@aol.com

Castrol GTX classic 20-50 oil zddp & Phosphorus.pdf ZDDP Egge Information.docx

[Los_Control]

I suppose words written on paper mean something, as long as there are facts to back it up with ...... not doubting Castrol GTX quality.

 

I used it for a few years in my daily driver vehicles. ..... With 2 rigs running, the car with the most miles never exceeded 6K miles per year. The truck had even less.

I always change my oil twice a year, spring and fall .... less then 3K miles on it.

 

I was always disappointed when I changed my oil and it was black in a few days. ...... Several years ago I was trying to sell a van that had a excellent running engine.

The prospective buyer that wanted the van just for the engine ..... The buyer took one look at the oil on the dipstick and never stayed around for me to start it up ..... The oil looks terrible. .... He suspected the engine never got any maintenance.

 

I have no good excuse why I still used it after that .... finally 2 years ago I swore off of it and am happy to look at clean oil when I check it.

 

A good possibility that it looks so dirty because it has all the extra additives ..... I really have no clue, I won't be using it in my engines though.

 

[desoto1939]

58 minutes ago, Los_Control said:

I suppose words written on paper mean something, as long as there are facts to back it up with ...... not doubting Castrol GTX quality.

 

I used it for a few years in my daily driver vehicles. ..... With 2 rigs running, the car with the most miles never exceeded 6K miles per year. The truck had even less.

I always change my oil twice a year, spring and fall .... less then 3K miles on it.

 

I was always disappointed when I changed my oil and it was black in a few days. ...... Several years ago I was trying to sell a van that had a excellent running engine.

The prospective buyer that wanted the van just for the engine ..... The buyer took one look at the oil on the dipstick and never stayed around for me to start it up ..... The oil looks terrible. .... He suspected the engine never got any maintenance.

 

I have no good excuse why I still used it after that .... finally 2 years ago I swore off of it and am happy to look at clean oil when I check it.

 

A good possibility that it looks so dirty because it has all the extra additives ..... I really have no clue, I won't be using it in my engines though.

 

Los Control so what oil brand and weight did you switch to use in your cars/trucks.  As you also know multi weight oil is a detergent oil and will get dirty with use. That is the makeup of the product.  Straight weight oil does not have the cleaning agents, so maybe you were picking up the oil that had been cleaning the engine over time. Did you also change the filter at the same time. I do know that the by-pass filters in the old style oil cans stated that you could go 5-8000 miles prior to replacing the oil filter, this is because the filter was not a full flow filter.

 

Not sure of why you had this problem, I am only reporting what I can and with the facts that I was provided.

 

Rich Hartung

desoto1939@aol.com

[Los_Control]

10 minutes ago, desoto1939 said:

Not sure of why you had this problem, I am only reporting what I can and with the facts that I was provided.

Please understand Rich, I'm not trying to say your facts are wrong ...... I'm only reporting my personal experience with using Castrol GTX on modern full flow engines where I always changed oil filter with the oil.

After years of use, I finally decided that the oil is simply not good enough for my 1991 chebby 350 vortec engine, or my 1993 Dodge V6.

I wont run it in my 1949 Dodge.

 

Sorry Rich, I just do not think it is a good idea to start a thread on oil. Will always be someone to come along and have a different opinion. Like myself.

I'm only reporting my actual experience with using the oil.

Castrol has been around for many years .... years ago we had issues with oil that had paraffin in it. Both Penzoil & Quakerstate had it. ...... I watched a buddy take the valve covers off of a fairly new engine, just filled with sludge. .... He was so disappointed in the oil performance, He bought a new crate engine to replace the new crate engine he had. ...... Just saying, he used Pennzoil ...... I'm not impressed with oils that have a bunch of extra additives ..... not all the additives are helpful, or do more harm then good.

 

What exactly on our old engines need a special oil, that the far superior modern oils do not provide?

Many people on this forum have fresh rebuilt engines and running modern oil with zero issues.

 

Castrol GTX is simply like a Dinosaur that forgot to die ..... like cockroaches.

 

 

[desoto1939]

I fully understand your input. I am not trying to persuade anyone to use any specific brand of oil. I know there has been alot of talk and posting regarding the use of ZDDP for the older cars every since it was removed because of the use of catalytic convertors in the modern cars.

 

I know some people add in the ZDDP additive and others do not. Yes I also agree that the oils we used in the 20's and up have improved dramatically with their protective additives and how we can refined these oil products with better standards.

 

I know people that are using the Purple brand or VR1 in their antiques and that is fine with me. I was just trying to point out that there are other brands that have the same qualities.

But I have seen anyone post the data to support what is in each product.

 

I am not a chemical engineer so I have to believe what the company posts and then everone can make their own opinion and use the product of choice.

 

Rich hartung

[Los_Control]

19 minutes ago, desoto1939 said:

I am not a chemical engineer so I have to believe what the company posts and then everone can make their own opinion and use the product of choice.

 

I agree with you 100% ......

I'm of the opinion that someone is paying for the reports, and typically the report will be written in their favor.

So these reports really do not interest me.

 

Recently we were told to wear a surgical mask to avoid spreading covid.

Mask were tried over 100 years ago and documented in reports they do not prevent the passing of a virus.

They Doctored up a report and sent it out just the same to wear mask.

A few years later honest reports are coming out that support the fact mask never did work ..... we all knew this 100 years ago.

 

All I'm saying Rich, I have been lied to so many times on fake reports slanted to support one side or the other ..... depending who is paying for it.

 

My opinion is strictly from my personal use of the oil over several years. ..... Does not mean I'm right.

 

As far as what modern oil I'm currently using ...... walmart supertech.

I have read up on it and it is only made in 2 plants in the USA ..... one is Mobil1, the other is Exxon ..... depends what side of the country you live on as to who made your oil.

Either way am satisfied with it ..... lately been wondering if they cut corners to get the cost down,

 

For a few Dollars more, can just switch to Mobil1 oil and quit thinking about it ......

 

[kencombs]

Just a comment about the history of zinc compounds in oil . During the early years of our flatheads, no oil contained that.   Only after the advent of overhead valves, with the added valve train weight and higher spring pressures was is added to oil formulas.   While it won't hurt anything (unless you have a newer engine and it's catalytic converter), IMHO there is no benefit either.   

As Los mentioned, the older oils with high paraffin content really left a lot of deposits, everywhere in the engine.   I've seen Y-block Fords with so much deposited inside the valve covers that the rocker arms were leaving impressions in the waxy stuff.   And, over an inch layered in the bottom of the oil pan.   But, OTOH, I've never seen an engine with a bearing failure due to that stuff.   Lubes good, for all it faults.