Tom, I coated the cam with the black paste ( don't remember which product, but specified for cam break in), and used Joe Gibbs LS30 5W30 high zinc oil for two years.
I then switched to Quaker state full synthetic 5W30. This decision was based on Rat540 oil blog oil film strength testing.
I had good experience with the Quaker State Ultimate Durability in my 2004 GTO LS1. Just did a cam / lifter swap at 81k miles and the old roller parts looked good.
Funny thing is I posted on his blog about my misfortune, and chastised me for even using the high zinc oil in the first place, stating that cause the wear !
The worn lifters are concaved, not " striped", not sure if that means they were rotating.
So, possibly running that oil on a HFT cam is the cause.
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