Sinister Diesel 2004.5-2005 6.6L Duramax, EGR Cooler – SD-EGRC-LLY


Product Highlights:

Sinister Diesel has reinvented the Exhaust Gas Recirculation (EGR) cooler with this great new model for the 6.6L LLY Duramax diesel engine with the same fit as the factory GM unit. When the internal brazing cracks and fails in the factory EGR Cooler it will allow coolant to be sucked into the intake manifold. From the manifold it enters the combustion chamber and usually results in a blown head gasket or hydro-locked motor with a costly repair bill for thousands of dollars!

If you’re tired of clogs and the possibility of a catastrophic failure with the stock 6.6L LLY Duramax EGR cooler, or if you just want to prevent future headaches from unnecessary maintenance, protect your investment in your truck with an upgraded Duramax EGR cooler from Sinister Diesel. Instead of the narrow internal cooling fins with brazed connections, we assemble each 6.6L LLY Duramax EGR cooler using high-flow stainless steel tubing with quality TIG welds and then pressure-test each unit to ensure reliability that a stock units can’t match.

The Sinister Diesel EGR cooler for the 6.6L LLY Duramax has been extensively tested at our California. It works flawlessly with the factory GM tuning without need for any modification and will not trigger the Check Engine Light/ Additionally, we guarantee that this upgraded EGR cooler it will work with any performance chip or tuner on the market. Installation is a simple, direct, drop in replacement on any 2004 and 2005 Chevy or GMC 2500/3500 with the 6.6L LLY Duramax diesel engine.

Vehicle Fitment

2004.5-2005 GM Duramax 6.6L LLY

Key Features

  • Stainless Steel Construction
  • Fully TIG Welded and Pressure Tested
  • Improved exhaust gas flow


*Special Order. Please allow for additional shipping time.

This will also add the following products to your cart:

  • Core Charge 175