"Fellow participants,
It has
"Fellow participants,
It has come to my attention through a discussion with my machine shop personnel that older engine designs that use flat tappets, such as Interceptor Y blocks, could see increased cam and tappet wear with modern oils.
From the Castrol web page, Ask an expert:
"Older engines that use flat tappets could be sensitive to reduced levels of phosphorous in oil formulations. It appears that 0.1% is about the cut off point, so oils for flat tappets should contain more than 0.1%. Phosphorous has been steadily going down as the amount of ZDDP (Zinc Dialkyl DithioPhosphate) has been reduced to ensure compatibility with exhaust after treatment (read Catalytic converters)."
From Shell Ask Our Expert:
"Older vehicles, especially like those you mention with the flat tappet cams, seem to experience less cam wear when using oils with higher levels of the zinc antiwear additive (ZDDP). For those vehicles, we recommend using Shell Rotella T oils, which do have the higher ZDDP content. Rotella T 30 has ~1200 ppm of ZDDP."
(note: 1200 ppm equates to .12% ZDDP)
So there you have it.
Ray"
It has
"Fellow participants,
It has come to my attention through a discussion with my machine shop personnel that older engine designs that use flat tappets, such as Interceptor Y blocks, could see increased cam and tappet wear with modern oils.
From the Castrol web page, Ask an expert:
"Older engines that use flat tappets could be sensitive to reduced levels of phosphorous in oil formulations. It appears that 0.1% is about the cut off point, so oils for flat tappets should contain more than 0.1%. Phosphorous has been steadily going down as the amount of ZDDP (Zinc Dialkyl DithioPhosphate) has been reduced to ensure compatibility with exhaust after treatment (read Catalytic converters)."
From Shell Ask Our Expert:
"Older vehicles, especially like those you mention with the flat tappet cams, seem to experience less cam wear when using oils with higher levels of the zinc antiwear additive (ZDDP). For those vehicles, we recommend using Shell Rotella T oils, which do have the higher ZDDP content. Rotella T 30 has ~1200 ppm of ZDDP."
(note: 1200 ppm equates to .12% ZDDP)
So there you have it.
Ray"