The 2006-2007 GM 6.6L Duramax LBZ's are some impressive trucks to say the least, but there's always a way to improve your everyday driving experiences. Our selection of speakers, subwoofers, and head units for the Sierra/Silverado's can give your truck's audio system a new lease on life and blow the stock speakers out of the water. These aftermarket audio upgrades feature much higher build qualities and give your tunes more range with deeper bass, sharper highs and cleaner mids. If you're looking to seriously bump up your bass, choose from our lineup of subwoofers that can practically fit any cab size out here. No matter what your intended applications may be, improve the sound quality on each of your adventures with any of the premium audio upgrades we have in store. GM Duramax Fitments: 2006, 2007 GM 6.6L Duramax.Submodel Fitments: WT, Custom, LT, LTZ, High Country, 1LT, 2LT, Pro, SLE, SLT, AT4, Denali.Some exceptions apply, please see individual product pages for specific fitments.