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Discussion Starter #1
I just recently changed the oil in my original WT 389 (1965) and am now wondering if this oil has enough zinc for my stock motor.
 

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I use VR1.

Most over the counter oils have reduced ZDDP. Check the service code. If SM or SN it will have reduced levels unless designated as a racing oil.
 

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Castrol GTX does not have the amounts of ZDDP needed for your engine. In addition, over the past several years, it rates at or near the bottom of all of the oil comparison tests I've read. Believe it or not, the cheap Walmart oils are near the top of these lists. I run Shell Rotella diesel spec in all my old flat tappet muscle cars, and have been for years. No issues, and cheap.
 

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I use Lucas hotrod oil......I am very happy! I am testing Sunoco CLASSIC oil in my Trans Am....seems like good stuff. Both oils have above 2000ppm zinc, which should be enough for our engines.
 

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Discussion Starter #7
I am running Valvoline VR1 10w-30....You can also use a more common oil and add ZDDP.
After reading geeteeohguy's report on the lack of zinc in the oil I was using, I got a bottle of Lucas TB Zinc Plus.
The tech told me I only needed to put half the bottle in for my motor's needs.
 

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I recommend reading some of the information on this subject on Bob the Oil Guy's web site. I did a lot of research on this subject using many sources Bob's being just one. My conclusion was that they are slowly reducing and eliminating zinc in most product lines. Most of todays detergent oils do not allow mixing of foreign ( to that specific oil formulation ) substances by keeping them in suspension so adding zinc is a waste of time and money. For my peace of mind and to eliminate any chance of damaging my motor I spend the extra money and use Joe Gibbs Driven racing oil ( HR2 10w-30 ) conventional oil. Why mess around ? Your cam will thank you.
 
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