Guys, my friend just got an 03 6.0L 2500HD. He has 2 questions. First, what kind of exhaust can he get that is not obnoxious, because I have heard many of the regular mufflers (Dynomax, Flowmaster) are very loud and he drives ~150 miles on the highway every day. Second, is there an aftermarket intake tube he can get. The stock one looks awefully kinked. Thanks for any info.

 

I have a 3-chamber Flowmaster, and I get a little interior resonance. It's not getting on my nerves right now, but it does every now and then.

As far as intakes, I personally run a K&N FIPK, but many people run the UPD intakes. There's a link on the front page of the Truck Performance section for the UPDs.

Hope this helps...

 

Below is a post I did several months ago, after changing the exhaust on my 2001 2500 HD x-cab 4x4 with the 6.0/auto. I have since added AS & M equal length headers, and it has actually quieted the truck down even more, and sounds very good now. Here's the previous post I made:

/My muffler shop installed the dual 3" in, single 4" out magnaflow part # 12594 on my HD, and utilized the stock 3.5" tailpipe. It sounded fine at idle, but when I took it for a drive, the resonance between 1500 and 2000 rpms was quite bad. This is the same muffler that the engineer at Magnaflow told me would have no resonance on this HD 6.0 I immediately called him up, explained to him that the decibels were not a problem, the exhaust was plenty quiet at idle, and even at full throttle, but just cruising around town between 1500 and 2000 rpms, was enough to drive a person crazy pretty quick. He said I could either try putting another 4" inline muffler/resonator part# 12770 right behind the main muffler and see if that took care of the problem, or put it back to stock and get a refund for the muffler, but still have to pay the labor charges. My concern was though, that if installing the second muffler/resonator didn't take care of the problem, I'd be stuck with paying for that resonator, and all the hours of labor the shop had spent working on this, and then have to put it back to stock if this didn't work. They couldn't guarantee me that it would work, so I basically decided to take the chance, and had the shop move the main muffler further forward, and installed the secondary muffler behind it. $385 dollars worth of mufflers, parts, and labor later, it does sound good now, and basically all the resonance is gone. Enough that I can live with it at least. I was more than a little unhappy with the engineer at magnaflow, that they are releasing this muffler as part of their catback system for these trucks, without a little more thorough testing. According to him, they're going to go back to the drawing board, and see about extending the muffler out to 30" instead of 22", and see if that helps the resonance problem.

As far as intakes go, I have the Volant air intake, and am happy with it. I've also heard good things about the UPD intake also.

Jason
Jason

 

Thanks guys.