There's not much in the 4" variety aftermarket. The issue is there is no space for the downpipe around the doghouse. If you want to run free on your trip kill the kitty and put in straight pipe or a test pipe and a high flow muffler. The stock muffler is also a bit restrictive. Without cutting out the cat there's not really performance gains to be gained unless you can get 4" all the way back to the turbo. That's my understanding anyway.
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2005 E350 RB 6.0 PSD for extended fun
1989 Landcruiser FJ62 for local fun
2011 VW TDI Golf for hwy fun
OK i have a 7.3 but i think the difference is not so much.
the 4" exhaust was still in when i bought the van and there also was a drone between 1800 and 2400. The preowner said that the exhaust gets some more mpg. No idea if this is true. But i am happy with the consuption. After changing the gear ratio i am in the drone area at highway speed .....and it is so bad that i am looking for a solution. One more muffler? I spend up to now nearly one week on surching what the drone causes. No solution in the moment. Next step is a muffler like the arow 4040XL. But it is hard to get here in europe and shiping costs are so high
So my resume....if you want a quiet comfortable ride stay with the oem one!
I have the 7.3 so a different beast, but my guy installed a magnaflow, I know they are avail for the 6.0L. I'm not sure if I remember what it sounded like before the swap, there's diesel clatter that covers up things anyway. I don't notice a particular drone, I do hear the turbo whistle, which I like. The 6.0's are generally quieter than the 7.3 to start with anyway I think, but swapping over to a 4" will help lower your EGT's and increase your HP/torque/mileage. I would recommend staying away from ones made specifically for off-road use, there are others that are designed to be loud and boast a throatier sound, from my experience, the magnaflows seem to be a good balance.
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'03 Ford E350 7.3L Diesel
(de)SMB'd Custom RB-50
Quigley 4X4 w/Deavers & Agile Offroad's R.I.P. package
CCV High Profile Pop Top
I think an important thing to remember when modifying the stock exhaust on the 6.0 is that the primary restriction is the cat. From the turbo to the cat is 3.5" pipe. From the cat to the tailpipe is stainless 4" from the factory.
Unless you can retrofit or fabricate a 4" downpipe there is not much point in a complete system. The best bang for the buck is to delete the cat and replace it with a straight pipe.
2008 Ford e350
Linear Mode
