what is it?

[spongebob]

that plastic cover on top of the engine, it says "6.6 turbo diesel" on it?
is it necessary?

[DmaxMaverick]

On early models, it was no more than a decorative cover. On later models, the cover incorporates a resonance baffle, to minimize intake pulse and turbo noise. Unlike the 6.5's, the cover doesn't create any negative effects.

[spongebob]

so, if i remove this baffle, will i hear that sweet sound of my turbo?

[DmaxMaverick]

so, if i remove this baffle, will i hear that sweet sound of my turbo?

Maybe a little more than now, but probably not real noticeable. If turbo whistle is what you're after, a modified airbox or aftermarket intake will do it.

[spongebob]

got a link to the modified airbox??? yes i love that whistle..

[DmaxMaverick]

got a link to the modified airbox??? yes i love that whistle..

I don't think the past methods will work on your 2006. Your airbox is different, being cylindrical. The old boxes were boxes, cubicle. You could drill the box full of holes, but that would encourage hot engine compartment air to enter it, and possible generate emmissions DTC's. An aftermarket intake would probably be your best bet. Blocking off the baffle engine cover would not likely cause any issues, and the result could me more profound than previous models. Removing the intake baffle on some vehicles (maybe not the Duramax) have a result of making them sound anemic. Give it a try. You can always restore it.

[spongebob]

thanks dmax..