I just bought a magnaflow muffler for my 2004 crewcab 5.4 I measured my tail pipe and got 2.87". I am wanting to put a stainless steel weld on tip when I install the muffler. Did I measure wrong or fo I just use a 3" and fill the gap with a shim? Any recomdations on a tip would be great. I am thinking a 3" in 4" out?

 

3" inlet 4" outlet. Have a shop expand the piping from your stock piping to fit the 3".

 

I was thinking about that just have to find out if they can do that with the tail pipe on the truck because I didn't plan on taking that off. Will have to wait till I get the truck out of the shop next week some time. Getting a P0315 and intermintant missfire on cyl 5 and 6 new coils and still the same.

 

They can make an adapter.