from what i read the 05 f150 5.4 oem exhaust diameter is 2.5 so if i was to replace the muffler what diameter would i have to buy? 2.5 or 2.25 ? if i went with the 2.5" would it just touch on the ends and not slide into eachother and have to be welded? and if i bought a 2.25" in/out muffler would it slide into the existing 2.5" piping?

whats the best thing to do?

andddd what is the stock exhaust metal made of ? is it steel or aluminum or wa? i have no clue havent really sized it up ahah

 

You can buy slip joints that will go over stock pipe and new muffler do not go to 2.25

 

I just bought a 2.5 in 2.5 out muffler and tip and took to shop to have them weld. When you buy the muffler, I am pretty sure the I.D. of the muffler is 2.5" and the O.D. of our pipes is 2.5. So it fits like its supposed to and then they just weld a seam for closure.

 

why would you not want to weld it? C-clamps are recommened for a temp fix until you can get it welded. I would weld everything if I could.

 

All mufflers come with flanged inlets & outlets, meaning their inlets/outlets slip over the pipe. Keep it 2.5". Stock is Stainless Steel naturally finished.

 

thanx! thats good to no, what about length? would i have to add more piping with different mufflers?

 

Ofcoarse. The stock muffler is 32"s, and if you put like a 14" Magnaflow on it, thats 18"s of pipe needed. Go by the mufflers body length because if you go my the overall length you will be 6"s short ( muffler inlets & outlets are 3"s ). The muffler inlet needs slipped over the new pipe, new pipe slipped over intermediate pipe, and tailpipe slipped over the muffler outlet.

 

ok well i went and bought a 2.5 ID muffler and a 2.5 - 3.0" tip, so i went out just to see if the tip would fit over the exhaust and it is the same size as the exhaust and wont fit over it, so i put it up against my new muffler and it wouldnt fit onto it either it was the exact same size like the stock exhaust, so i guess the exhaust is 2.5 ID not OD am i still going to be able to install this? well.. the shop is on monday but will it still work?

 

The reason it wont fit on the muffler is because the muffler is flanged to a larger opening, i.e. it should butt up because the tip is also flanged. You got the right stuff trust me. I bought the exact same thing you have only my tip is 2.5"-4". You are gonna love it once the shop installs your muffler and tip and they crank it up to pull it out.

What is your tip and muffler numbers and I can verify it for sure real quick.

 

but my tip butts up with my tailpipe.. and my tip butts up with my muffler.. thats what im saying it seems like its all the same size and seem to be all 2.5" ID

 

I think the stock tip is also flanged a little. If you look at it where it bends to start heading out to the factory tip, look and see if it doesn't flange to a bigger size for the 14" or so. I think it does. It should be 2.5" from the back of the stock muffler and all the way to that bend then get larger for the stock exit.