Duramax question

[tajensen]

A friend of mine was asking me if it was a good idea to straight pipe his Duramax. I told him that removing the muffler would probably help with EGTs and possibly improve his performance and milage. He went to have the job done at a local muffler shop (reputation unknown) and they said it was a horrible idea. The guy claimed that removing the muffler causes Duramax's to suffer on milage. Is this guy full of it?



-Tim

 

[SRadke]

I have no personal expereince with them but I've heard a few and they're really loud.



-Scott

 

[turboost]

The muffler on them is pretty restrictive I think. I removed mine and with a programmer I could get 20mpg doing 90mph on a couple trips. Never got below 16mpg in town. All were unloaded.