MBRP 409 SS vs. 304 SS

[JMA1181]

I am going to order an exhaust for my truck. I was planning on getting the MBRP 4" Turbo Back 304 Stainless exhaust but after speaking with a guy here that works on diesels he has tried to get me to just go with the 409. I live in Indiana so there will be salt on the roads in the winter time so stainless is a must in my opinion. I only want to do an exhaust once as I had to have it done twice in 5 years on my last truck. What is the difference between the 409 and the 304? I had always thought that the 304 had a polished look all the way to the turbo. Is this the case or am I wrong in my thinking? Any help would be appreciated.
Thanks, Jordan

[3ddiver]

304 is a higher grade of stainless and I believe the MBRP is polished. It will not tarnish like the 409. I live in Illinois and I am getting ready to put the 409 on my truck. I personally dont think that you will have a problem with 409 unless you want it to shine all the time.

[JMA1181]

So the 409 does not shine all the time?

[3ddiver]

I dont think so. I believe it will get a yellow/brown color like the factory exhaust. The tip is 304 so it will shine all the time.

[LvTitan]

i have the 4" turbo back offroad system in 409 and i can tell you that ONLY the muffler is polished. matt told me if you order a 304 kit from mbrp that is the polished one. it is also a higher grade of stainless, but you will be just fine with the 409, you will probably never have to replace it.. it does not really look rusty and tarnished as bad the factory exhaust, but it is definitely no where near the look of the 304.
i can email you some pics of my exhaust if you want.

[barry1me]

409SS will be sufficent for sure. 304SS is a higher grade Stainless it will last hold up to corrosion and thermal degradation much better then 409SS. But the Factory exhaust is a 409SS and it has to be validated for a 15 year 150K mileage durrability cycle, so 409SS is adequate for our trucks

[BigGreen06]

I've had my 409SS kit on my truck for about a year now and the only thing that still shines other than the tip is the muff delete pipe that I put on about a month ago. The rest of it is pretty well degraded by the high temps that our trucks see.

-BG06.

[720Deere]

409 will last, but it ain't going to be pretty. It will come with a semi-gloss look, but the first winter event will have it spotted and even pitting in no time at all. I believe that the 409SS that MBRP uses is inferior to the stock Ford system. My stock pipes did not "rust" like the MBRP does.

If you only want longevity go 409 if you want maximum longevity and looks go with the 304.

[yamaharider103]

so there's 3 types of exhaust.....409ss, 304ss, and aluminized can some one tell me the diffrence. and wich one is gonna last in harsh conditions (Salt, Sand, Winter)

[Raul@Stealth Automotive]

for harsh cond i would only go with 304S.. the AL would deteriorate very quickly with those conditions and the 409s wont deteriorate but it wont look shiny......