The Flex Plate Clamp issue can affect any 928 fitted with an Automatic transmission from 1984 onwards.  The problem is where Porsche changed the design of the clamp so that in some circumstances the drive shaft can move forward; putting huge pressure on the flex plate; which can lead to Thrust Bearing Failure (TBF).  This is a catastrophic event, leading to the total loss of the engine and huge bills for the owner.  The solution has been regular checking and relieving of flex plate pressure, as described in detail in this PDF.

Lately 3rd parties have come up with stronger clamps in an attempt to solve this.  Now UK company Ritech Systems has come up with a new solution, which is designed to stop the clamp moving forward by physical means.  Click on the picture for more:

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