The heater grid was installed on these engines to allow them to reach operating temperatures quicker during cold starts. Reaching operating temperatures quicker means the engine would burn fuel more efficiently which in turn reduces emissions. For this reason these are sold for off road use only.
The Duramax LBZ & LMM still used glow plugs, meaning cold starts will not be compromised with the removal of the grid heater.
Why remove the grid heater?
Reduce airflow restrictions
Allows more air to pass through the intake manifold at a lower resistance
The grid heater spacer typically takes about 30 minutes to install. It will most likely cause a check engine light which can be turned off with programming. Trucks in warmer climates (above 40 F) might not see a check engine light.
