I think the cats handle most of the back pressure. Not sure about the warranty though. They will probably try to contest warranty work any way they can.

All I know is that I paid for a high performance engine and it should sound like one. Ordered mufflex this morning.

 

I have no loss of low end performance on mine, it actually feels like it woke it up some.

 

I also have to agree, it does feel like she woke up a bit with the new muffler.It also seems to get a little better mileage now as well, maybe due to a little less back pressure??
Either way I am happy enough to put the same muffler set up on the wifes truck.

 

I put on the DOD18M yesterday, and I feel the truck is a little more sluggish at low-mid, maybe slightly more power at high rpm, just seat of the pants feel. However the computer will need some time to learn the new flow rate, I think in time it will get better... Also kind of wish I would have went with the 14 inch, but we will see once this one burns in.

 

Thank Stealthgoat for the review on the 24". i have been holding off on getting one until I heard something good or bad about it. Like you, I want better sound, but quite on the highway. Sounds like a good one for me. My truck has 10K miles on it so I bet taking the system apart will be tougher then yours was - lol

 

Twist,
Glad I could help you out, I was in the same boat as you, I couldn't find anyone who had the 24's on their truck, But I'm very glad I went with the 24, you get great sound on take off and once up to highway speed it quites down just like the stock muffler. I don't think you'll have to much of a problem getting your old system apart, the clamps that they use from the factory are not like the old style that pinch a small bead into the pipes, the new style of clamps are like 1 1/2" wide and don't crimp or pinch into the pipes at all.

Good luck with your new system.

 

How loud would you rate the 18" on the highway? Is there any drone? Rumble is one thing but a harmonic drone I would want to stay away from. My 05 had that after a MBRP Cat Back at right around 2,000 RPM. Had to install a Resonator to fix but then lost a bit of the rumble.

 

My stock exhaust has really come along this past week. 2700 miles on it. Just wondering if the 14 will be too much. I'll post a review in the FAQ section

 

Topgun,
There is a guy that has a video on youtube with the 18"s and he has the dreaded highway drone, that is what made my mind up to go with the 24"s

 

I saw that one. Thanks.

On the 24", is there a noticable difference over the stock Sport muffler?