new exhaust
Elder User
Joined: Dec 2006
Posts: 559
Likes: 4
From: On a farm.
The actual noise level won't be bad, but my experience is that at certain loads and rpms, you'll get some unpleasant and annoying tonal qualities. Mine happened at the trucks favorite "low cruise" speed of 60 mph. There isn't much difference in restriction between a good free flow muffler and no muffler. Saw that recently on a Duramax truck, where the truck actually LOST power with the exhaust uncapped (about 5 feet back from the turbo) compared to with a free-flow 4-inch system with a straight thru muffler. Each truck is different and I think the electronic trucks, like the DMax,may respond differntly to backpressure changes. Anyway, my point is that if the tone bugs ya, like it did me, don't be afraid to install a muffler to use as a resonator. Make it a straight thru type muffler for minimal backpressure.
