2011-2019 GM 6.6L Duramax EPC Blocker

GM 6.6L Duramax EPC Blocker, 2011-2019 LML/L5P Allison transmission

This easy-to-install kit solves a big problem with the 2011-2019 Allison 1000 transmission... low mainline pressure.

Mainline pressure is created by the transmission's oil pump. Mainline pressure is directed by the valve body to the applied pistons and creates clamping force on the clutch packs, allowing the clutch packs to clamp quickly and completely. Reduced mainline pressure, or not having enough mainline pressure at the right time means reduced clamping force and there won't be enough to hold the torque of the engine. When clutch packs slip they generate excessive heat which destroys the clutch pack material.

The purpose of the EPC circuit is to modulate mainline pressure. Mainline pressure in a 2011-2019 Allison 1000 varies between 80psi to 230psi depending on driving conditions. When applying throttle to accelerate the mainline pressure will rise from 80psi up to 230psi. After the shift, the pressure drops back down to 80psi. At 80psi the clutch packs have barely enough clamping force hold the torque of the engine. The time it takes for the EPC circuit to close and allow the mainline pressure to build is too slow to effectively stop clutch plate slippage and premature wear. Installation of the EPC blocker allows the mainline pressure to be fully available at all driving conditions like the 2001 to 2010 Allison 1000 transmissions.

The EPC blocker kit quickly installs between the EPC solenoid and the valve body. There is no need to remove the valve body. Just drain the transmission fluid, remove the oil pan, and install the EPC blocker. Once installed, the EPC blocker will allow all the available mainline pressure, up to 230 psi, to reach the applied pistons and clutch packs at all times.