04 3500 exhaust reccomendations

[JRhinehart]

My 04 3500 quadcab 4x4 shortbox single rear wheel rusted the muffler at the tailpipe connection at 135K miles. I will probably just replace the muffler, but may go with a muffler/tailpipe combination if it will really make a big difference. I have only put a Bully Dog triple on it with no other mods, so what would be the best bang-for-the-buck on exhaust? Would it be a good time to get an air box also? Also, it has the 305/555 engine in it.

 

[LRutigliano]

I started out with a new Magnaflow 36" long muffler and was completely happy with it until I noticed my 3. 5" downpipe at the turbo was dark brown (from what I assume was alot of heat).



I researched and ended up with an MBRP 4" turbo back 409 stainless system. Paid $412 delivered to my front door and installed it very easily by myself.



There are alot of quality systems out there. Do a search on exhaust and go for it !!



I also tried quite a few different intake systems (aFe 5-ply stock filter, aFe stage 2Si system, Amsoil Eea stock filter) and ended up with the PSM Buick cold air kit, DPP cool red hose and aFe 7-ply stock filter and am happy with it.



Please look at my readers photos for what I've done to the truck and to get you started on some ideas.



Good luck and have fun !!



Louis



p. s. once you start, there is no turning back as each mod will get you hungry for the next one...

 

[CToney]

I would suggest an entire system. You should have only 3. 5". Go with a full 4".

 

[JJPage]

If you want to go with a whole new system, might I suggest you change out your cast elbow on the back side of your turbo, to one from an 04. 5 or newer. The one on our 03/04's go from 4" to 3. 5" approx. the newer ones are 4" all the way through.



Then purchase a system for the newer model, but make sure you tell them what you did, so you get a turbo back system and not a cat back system.



I did not do the cast elbow at first, purchased a MBRP 5" turbo back system. Then in an attempt to lower egt's and spool my turbo better, I changed out the cast elbow, now I also had to purchase a new downpipe, because one for an 03/04 will not fit the newer elbow. Should have done it right the first time.



I like my 5" MBRP, but it is aluminized, not stainless. Bryan Howell at Diesel Power Products, sells some really nice stainless Diamond Eye systems, both 4" and 5". If MBRP still does not offer the 5" in SS, I would go with the Diamond Eye. Jess

 

[bkaiser]

The exhaust on my '03 failed at the muffler inlet also. I used it as an exuse to upgrade.



I did the full 4" upgrade. Bought an elbow for an '05 and the ANSA/Silverline 4 inch exhaust for an '05. They advertise this system is for off road use only because it eliminates the cat. Since the '03s don't have a cat, it is legal for our trucks. What I found nice was having a system that wasn't pieced together and all from one source.



I have found the Silverline to have a bit of drone at 2100 RPM, but that's where I shift anyway. EGTs dropped a little, but I was mostly looking for a clean install and more exhaust tone.