Well, just got done doing some work under my truck now that its getting nice out - didn't realize how much of the exhaust was still 3" that the PO never replaced. Right now, its 3" until the output of the transfer case for the most part, and 4" back.

I'm guessing going to a 4" will be a noticeable difference over the 3" on there currently. I do run it pretty heavy, so anything to help power / mileage / EGTs is great.

Truck is a '96 3500 5-speed dually, mods are (as far as I know) #11 fuel plate slid forward, BHAF, and boost elbow.

The question is - who has the best price on just the downpipe assembly and whatever extension is needed to get it back to that point? I really don't want to go the total exhaust replacement route, as the rest is still in real good shape.

 

Check out Flo-Pro and Expandit.

 

I have a straight piped 4" MBRP from the turbo back. Works fine for me and the freeway noise doesn't bother me. Not sure about the neighbors when I go to work every morning .

Around 70 on the highway i'm usually hittin 700-800 degrees.

Towing 6,000lbs at 70 usually around 950-1,100 degrees.