Muffler Removal

[RFriis]

I have a 2005, 5. 9, 2wd, 48RE, quad cab, long box, pac brake, guages. Am thinking about removing the muffler as a friend says he improved the mileage about 2mpg by doing so. I like the quietness of the truck now and am wondering how much louder it will be inside the cab with the muffler removed.

Roy

 

[AH64ID]

It will be considerably louder, with just the cat I had a bit of drone towing as well. .

On a side note you probably won't see any mpg gain in real world numbers. The exhaust on these trucks flows pretty good, and doesn't account for much loss.
I have ran 4 different exhaust setups (including stock) and have not seen any mpg change with any of them.

 

[TimothyLong]

If you like the sound of the truck now with the stock muffler, you're probably not going to like it without a muffler. It's going to be plenty loud. I have the Banks Monster exhaust on mine and it is louder than the stock muffler, but not unbearable. Mine is a bit louder than stock at idle and I get a bit of a drone inside the cab when calling for power or at highway speeds of 65mph or greater, but nothing that I really mind. If you're looking for a fuel mileage bump, I'd go with a performance muffler. The performance mufflers, like my Banks Monster Exhaust, are basically straight through mufflers that open up into a resonance chamber. That help slow down the exhaust gases, thus dampening the sound. The stock mufflers have an S-shaped bend in them and are packed with a buck of dampening material to quiet the exhaust down. It's the S-shape that cause the back pressure robbing you of some fuel economy and power. Getting a straight through performance muffler will fix that and keep your neighbors from wanting to shoot you every time fire the truck up.

 

[MChrist]

I've toyed with exhaust combinations on just about everything I have ever owned, and of the vehicles I've modified and dyno'd, there has NEVER been more than a few percent peak horsepower gain by using a LOUD muffler over a stock muffler. Remember, that's at peak. So unless you are a drag racer, or sled puller, you won't notice any real power increase, only a sound increase. It will sound cool for a while, until you go on a trip. Or tow.....

 

[TimothyLong]

Okay, just realized you have a cat in your exhaust system. In that case, performance muffler or no muffler probably won't do a whole lot for you. My '03 doesn't have a cat and the exhaust system change helped me.

 

[zzman]

I just have straight 4" exhaust no muffler or cat, the sound isn't that bad but you can hear it. From the right rear it is pretty load for the cars you are passing.

 

[Southbound]

I removed my muffler for a straight through muffler which helped with EGT's and in my opinion sounds a little better (no drone). Note: I also removed my CAT for testing purposes... ... . still testing.

Southbound

 

[HHhuntitall]

I bought an '03 used a few years back, and loved the truck, which exploded this winter, I might add. But when I first got it, it had a 20lb propane tank welded in place of the muffler, with a pipe welded into the side to exit out in front of the duals. I didn't care for that, and bought a SS exhaust system from Summit. At the initial install, I installed the straight through muffler backwards, so it would sound cool, right? Well, I towed a trailer the next morning to take my horse to the vet, and when I unloaded him, he kept shaking his head and cocking it when I talked to him. The poor sucker was half deafened!! I made it home, turned him out, and went straight to my shop to reverse the muffler. It's still plenty loud, but it won't deafen the animals in the trailer anymore. Also, if you take the muffler completely off, it will definitely be heard in the cab. You'll have to turn your radio up at least three more notches to hear it the same. If you like the way it's quiet now, I wouldn't do take your muffler off. I don't think you will see much performance gain. As for your friend, I'd bet the reason he's getting better mileage is that he can "hear" himself getting on the throttle, and is backing out of it, thus the better mileage. Just my opinion.



God bless,