One of the most common failures of the 68RFE six speed automatic transmissions is case failure. And even if you build your transmission for increased power, this will still not prevent against the case cracking. Many will argue that adding an aftermarket transmission pan will alleviate this issue as they are built stronger than the factory stamped steel units they replace, in turn providing rigidity to the case. While this may help, its still not enough. The only way you can rest assured you will not be left with a gaping hole in the side of your expensive transmission is with the installation of a case brace.