dnlow

A new muffler back in the day increased mileage a bit because backpressure would decrease and the vehicle would run a bit lean. The problem is with today's cars the computer will just adjust the air fuel ratio and many have seen a slight decrease in mileage.

Or something like that...

If it is important to you, you should look up some info about it.

Rusty Luck

It's not super important but I figured if I could kill two birds with one stone, why not? You know?

UWswimmer

I have an 04 f150 5.4L with 162,000 miles on it. At the beginning of the summer did a muffler swap and installed a magnaflow 18 in oval muffler on the stock tubing, sounded great, low rumble, no cab drone at all. Sounded how a v8 pick-up should sound from the factory, but no MPG gains which is fine because the fact i own the truck i do means i dont care too much. In the last 3 weeks i have put new plugs in, new exhaust manifolds (mine were leaking,) and removed and cleaned my throttle body and MAF. All that gave me an added 2.5 MPG and my truck perked right up as if it took 3 years off its life. 2.5 MPG might not seem like much but thats over 60 extra miles per fill up. To sum up, keeping your truck well maintained is the best way to extend the trucks life and maybe gain back lost MPG, things like new mufflers and CAIs dont do much on their own without tuners and further mods and money.

Iv also grown a little bored of my exhaust for now, i dont want to set off car alarms, attract police, or cab drone myself crazy but i want more rumble and a bit more volume, the 18in magi is not much loader than stock. Iv bought a SS 3in tail pipe and intermediate pipe from summit, and a magnapack to shove in there to complete my self-built cat back for about 200$, it will be here on tue, I cant wait to weld it up and hear it growl!

Nero

I just installed the MBRP T409 stainless with a single rear exit (in the stock position). I had seen the exhaust in a couple of YT vids and made my decision from that. It looks great, but frankly, it's a little louder than I wanted, but I can live with it. It comes to life like a race car but it settles in. It drones a little at 60-70. I can say I'm happy but I really wanted a little bit more of a rumble.

bryank734

I have a cutout after the Y and its not loud at all unless your towing heavy loads. And I can still go to factory quiet.

Novo

I did a Flowmaster series 50 with 3" pipes and it sounds pretty good.

Rusty Luck

So I looking into a inexpensive bolt on cat-back exhast any suggestions? I saw this http://www.jegs.com/i/JEGS+Performan...31112/10002/-1, I know its aluminium but I'd paint it with High heat paint and I live in Texas, so no salt and stuff. Things don't corrode easily or fast. Suggestions are welcome, still trying to keep the price low.