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Using Synthetic Oil with Non Roller Bearing Type Tappets
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Using Synthetic Oil with Non Roller Bearing Type Tappets
I've been advised to not use any synthetic oil for my rebuilt '64 T-Bird's 390 engine because the tappets are not roller-bearing types. It doesn't seem right with all your higher specs. Can I?
-- Bill Hilliard, Golden, CO
There have been some concerns voiced by bloggers that the new GF-5 oils which have a reduced ZDDP level to protect catalytic converters have caused problems in high performance race engines with sliding tappets. We cannot confirm these issues and have been told by the OEMs that 800 ppm (GF-5 level) will protect both older and newer engines. If you prefer a product with a higher level of anti-wear performance, there are a number of Mobil 1 synthetic oils that have higher levels of phosphorus. In case you prefer oils with a higher phosphorus level please refer to the attached list for products that have higher phosphorus.
Answer updated April 2012
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