Chad81

http://www.dynomax.com/part_view.php...450&engine=5.4

It cost $525 installed, all I can say is that I'm extremely disappointed. It's just too quiet, at idle it's barely even louder than stock. Around 3k RPM it's very disappointing to say the least, I don't like extremely loud and obnoxious exhaust like Flowmaster, but this system just sounds pathetic. Avoid the Ultraflow Dynomax at all costs, in the next year or two I'll likely replace the exhaust with a Magnaflow system and Magnaflow cats.

jerrybizzle

Just swap the muffler portion to a dynomax bullet. With the insulation on these trucks it isn't overly loud. Sounds good outside and can still conversate inside and hear the radio.

Tradesman

The Dynomax that was on my truck from the previous owner was so frikking loud I had to raise my voice to have a conversation with my passengers. Glad that it felt apart and I replaced it with a Borla. I don't know which series Dynomax was in my truck but it was a single in, dual out all mandrel bent but made of 400 series stainless that corroded to s**t. After seeing it all go to hell I could never recommend Dynomax to anyone. Even if it sounds great, spending a couple hundred dollars on something that'll fall apart shortly is pretty bad. I'd recommend Borla Pro XS if you want loud.

Chad81

Mine definitely isn't loud, it's barely audible over the radio turned 1/2 way up. I should've went with Magnaflow.

Oneill_1952

I have the magnaflow 18" cat back and when i first had it put on it wasnt as loud as i would have expected...i actually liked it and had a lil bark to it but nothing to turn a head it....4 weeks later its getting more and more of a rumble to it..expecially on first start up... so maybe give it time and see what happens?

blue thunder06

Definitely agree with tradesman, since you don't want aggressive loud I'd either get the si/do setup or si/so dumped with a pro xs muffler

That's how mufflers typically work, a little quiet when they're brand new till you break them in. Mine was a bit quiet at first, just took a little bit of time. Now it doesn't matter how I'm driving, it's got a much louder tone to it. Still dreamin about that borla pro xs though

Especial86

iTrader: (1)

The longer the muffler, the quieter it will be... I've got a magnaflow 12288 18" SI/DO and it's the perfect no drone muffler that still gives you grunt when you want it. I've got clips on you tube if you search the part number, you'll find em.

When it comes to stainless just think of the name, it stains less. It does not mean its impervious to rust, it just means it will stain less... I would still coat the exhaust with some exhaust paint, especially the welds.. I've seen great stainless setups bite the dust quick because people think its rust proof... It's not...Coat your pipes and keep your stainless tips polished and it should last a lifetime... The muffler will inevitably rot out from trapped moisture inside, especially if its a glass packed muffler... That's why it's a good idea to clamp and not weld your muffler.

Tradesman

Pro XS is bloody loud! I agree, my Borla was quiet at first but now it has a growl to it. The same growl it had at 3000RPM is what it is at idle now, which is good enough for me.

I think you are completely incorrect regarding the capabilities of stainless as well as the construction of exhausts. There are different grades of stainless. 400 series stainless has almost no chromium and nickel content, which is why after a period of time they will go to ****. Most factory exhausts these days use 400 series stainless. The Dynomax that crapped out on my truck used 400. 300 series as used on my Borla will not corrode. 304 (great), 316 (superb) and 321 (excellent) are all high grades of aerospace stainless that won't corrode under conditions that you would see regardless of where you live.

You look at 600 series Inconel and that stuff is what they put on space shuttles and Formula 1 cars. Not like any one of us can afford it, but that puts 300 series to shame, and even then 300 series is generally more than enough for us anyways. Stainless comes in so many different grades it's important to choose the correct grade for the application.

I've seen muffler construction that used crimps, welds and hex screws. If you look at low end exhausts (Flowmaster, Magnaflow) they crimp their mufflers. You look at higher end exhausts (Corsa, Borla) and they weld their mufflers. Very high end mufflers (Akrapovic, Kriessieg) use hex screws. Crimps are used because it's cheap, it's fast and it works for a limited amount of time. Welding a muffler takes more time and requires an experienced welder or a welding robot. Both add cost to the manufacturer. Hex screws are used on mufflers so the muffler's internals can be adjusted and/or removed. This is what you'd see on vehicles that hit the race track. Certain race tracks have a decibel limit and you add or remove more sound deadening material and install baffles on the same muffler, thus requiring the use of hex screws.

As far a coatings are concerned, it depends on what you use to coat your exhaust as well as how you coat it. Baked on coatings that are applied at 300 degrees Celsius or higher are the highest quality coatings. However, that need is not necessary on 300 series. 400 series it is a good idea, and any type of aluminumized steel is a waste to coat as coating it would cost more than upgrading to a stainless.

Especial86

iTrader: (1)

I'm positive stainless will corrode, rust, and stain when not cared for...If you are suggesting stainless is impervious to degradation, and not in need of care or maintenance, then you are wrong. It will stain....

kanga2311

Tradesman, not all Flowmasters and Magnaflows are crimped, either. I had a Flowmaster super 44 and that was fully welded. Then when I was shopping for a cheap si/so muffler (cops were hassling me), I found a Thrush (Magnaflow, I believe) fully welded, also. The super 44 was painted mild steel and the Thrush was aluminized steel, but still welded.