The factory intercooler on LBZ and LMM Duramax trucks is adequate for stock power levels — but once you add a tune, larger turbos, or increased fueling, the stock unit becomes a restriction that limits power and raises EGTs.
WHAT AN INTERCOOLER DOES
- Cools the compressed air from the turbo before it enters the cylinder
- Cooler, denser air means more oxygen per cycle = more power
- Reduces EGTs by lowering combustion temps
- The factory unit is a bar-and-plate design with limited core volume
WHEN TO UPGRADE
- When you’ve added a performance tune and feel EGTs climbing under load
- When boost pressure recovers slowly after a gear change
- When making 400+ rwhp on a tuned LBZ or LMM
WHAT TO LOOK FOR IN AN INTERCOOLER
- Core dimensions: larger core = more cooling capacity
- Bar-and-plate construction (stronger than tube-and-fin)
- Proper inlet/outlet sizing to match your charge piping
- OEM fitment — replaces the factory unit without modification
POPULAR OPTIONS
- PPE High-Flow Intercooler: Direct-fit, significant volume increase over stock
- Mishimoto Intercooler: Lighter weight, excellent thermal performance
INSTALLATION TIPS
- Inspect all intercooler boots during installation — replace anything that looks tired
- Torque all clamps evenly — T-bolt clamps are preferred over worm gear
- Pressure test the system after install before driving