The coolant pressure inside the engine
block can reach 70+psi at high rpm before the thermostat fully opens. This
will cause a corroded frost plug to leak. The BD rear frost plug is able to
be seal the leak without the need to hammer out the old frost plug. We
recommend installing the rear frost plug plate when the transmission is
removed. The plate can be installed with the transmission in place, however
the surface finish on the back of the motor is critical and must be checked
prior to use.

Works with the frost plug in place, blown out, or leaking
No need to punch the old frost plug out
Utilizes one large #333 O-ring
Works with and without a TCC crossover tube
Five flanged head bolts to keep the coolant contained
6.7L require the bellhousing support bracket to be removed
Perfect time to install one is when the transmission is removed!