Building an '08 LMM Duramax

The radiator support also had to come off, which was more of a time sink than it was difficult.

With the support out of the way, the radiator was tilted and the factory intercooler was lifted out of its resting place. It helps to have two people if you're going to be doing this.

Note the intercooler tank curving around the radiator (arrow). This means that you can't just pull it straight out; instead it must be tilted and lifted up and out.

The intercooler coming out. Notice the plastic tank on the passenger's side.

With the stocker out, it was time to put in the Banks unit. With improved inlets and outlets, high-flow intercooler tanks, and a greater airflow capability, we were looking for 2-3 more psi of boost from the intercooler alone.

The Banks unit fits just like stock, with no parts trimming or adjustments needed.

With the new intercooler installed, it was time to bolt-up the radiator support, the hood latch, the lights, and the grille. Again, it was more time-consuming than anything else.

With more punch coming from the engine, an upgraded exhaust was just what the doctor ordered. The Banks exhaust system features metal cuffs that are welded around vent holes where fresh air is drawn in, creating a venturi effect that is said to cool the exhaust gases more effectively than the stock design during the DPF's active-regeneration cycles.

The Banks kit attaches after the DPF, and features a high-flow Y-pipe that splits into dual exit pipes.