Quiet When You Need It, Rowdy When You Want It

The Glory Days Speed Shop Thunder Muzzle

Valved exhaust systems have been popular in the gasoline world for years, and honestly, it makes sense. Sometimes you want the car quiet and civilized. Other times, you want it to sound like it’s about to get you a written warning from the local police department. Diesel guys haven’t had as many clean options in that space, which is what makes the Thunder Muzzle such an interesting piece.

Available in both 4-inch and 5-inch configurations, the Thunder Muzzle is essentially an adjustable diesel muffler that lets you change the personality of your truck with the flip of a switch. Closed, it acts more like a traditional muffler. Open it up, and the internal pivoting pipe creates a straighter path for a much louder, more aggressive exhaust note. You can also adjust it between the two, giving you more control than a basic muffler or full straight pipe setup.

It’s made in the USA from 304 stainless steel, rebuildable, and built around a patent-pending design with an external actuator that rotates the internal pipe. The end result is simple: quiet when you need it, rowdy when you want it. For a diesel truck that tows, cruises, idles through town, and still needs to party every now and then, that’s a pretty slick setup.

PHOTO BY GLORY DAYS SPEED SHOP