PPE EPC SOLENOID BLOCKER 128041119 | 2011-2019 Duramax 6.6L LML/L5P

The PPE EPC Solenoid Blocker is designed to address a common issue in 2011–2019 Allison 1000 transmissions: insufficient mainline pressure. Factory line pressure can drop significantly after shifts, reducing clutch clamping force and increasing the risk of clutch slip, excessive heat, and premature transmission wear—especially in towing or higher horsepower applications.

This simple upgrade helps maintain maximum available line pressure to the clutch packs, improving holding power, shift quality, and overall transmission reliability.

Key Benefits:

• Increases clutch pack clamping force
• Improves transmission shift quality
• Helps reduce clutch slip and heat buildup
• Supports higher horsepower and towing demands
• Alternative to transmission line pressure tuning

Features:

• Easy installation without removing the valve body
• Installs between the EPC solenoid and valve body
• Maintains available mainline pressure up to 230 PSI
• Ideal for towing, performance, and heavy-duty use

Installation Notes:

• Requires draining transmission fluid and removing the transmission pan
• Valve body removal is not required