tominiowa,
OEM auto producers put pressure on oil companies to stop including extreme pressure lubricants in their motor oils because it was costing the OEM's for warranty claims against them as a result of extreme pressure lubes rendering catalytic converters ineffective. This was as the OEM's were moving into roller cams anyway, and extreme pressure lubricants are not needed with a roller cam. As you can imagine, there was an onslaught of cam/lifter failures in motors using the flat tappet technology. Here is a tutorial that will hit all the specifics of the problem.......
http://www.crankshaftcoalition.com/w...ips_and_tricks

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