I am new to this board having recently took the possession of a F-150 4X4 Sport with a 4.6 and 5-speed.

Anyway, I love everything except the quiet exhaust. Anyone on here modified the exhaust on a warrantied truck? Damn that muffler is huge...looks like it belongs on an RV.

Nothing radical just thinking duals out the back with DynoMax's or Flowmasters for mufflers. My T-Bird and Mustang (yes, I kinda like Fords) both have V8's and mufflers so I am kind of spoiled. However neither were under warranty when I bought them.

 

Run a search...and all your questions will be answered.

 

I got exhaust on my 2001 F-150 after about 1000 miles....to allow for some sort of break-in period. I was also worried about the warranty. According to my service manager....who is actually helpful, who'd have thunk it????...that will only void the warranty covering the exhaust. So I did it, and glad I did. Now it has the rumble it should have had from the factory. Oh yeah, SI/DO 50 series Flow with some nice chrome tips out the back. $300 dollars at the local muffler shop with a 2 year warranty.

Like 02XLT said, though, there are many other posts on this very topic.....especially in the Aftermaket Exhaust System Forum...

 

I've got the same truck as you, except for the auto trans. I did my exhaust at about 2000 miles. It will not void the warranty, except of course on the factory exhaust which you'll be cutting off anyway.

I would think the catback or modified exhaust is probably the single most popular 1st mod...with the possible exception being an intake kit. Still, it's probably close between those two.

If you want it, do it and don't worry 'bout that canoe of a muffler you take off. It makes a nice wall hanger. I mounted mine over the fireplace next to a nice 8 point buck.

Good luck with the new truck.

Natty

 

Well in talking with you guys and others, I think I will try to seperate at the present exhaust junction which is directly after the Y back into another Y with two single I/O mufflers in basically parallel paths and then run each out the back around each side of the spare tire and under the bumper. Then after 30,000, cut both Y's out and run straight pipes with either a H or X in the system around where the factory Y is located now. Sorry if that is confusing. Basically my bottleneck will be the pipe between the two Y's.

2 1/2" the whole way.

Any problems with this scenerio? How much low end torque will disappear?

 

Kind of sounds like overkill, if you're going to leave the stock Y in place just run a SI/DO muffler. It would be about the same thing, but cheaper. Later if you want to dual it out, just have it redone. I've had true duals for a couple of years now, but I'm ready to experiment again I'm thinking of putting a custom(better flowing) Y pipe in, then going with a SI/DO muffler. I just read where someones exhaust just lost him about 17 HP on the dyno. They had nearly the same exhaust as my present one, but with an X-pipe.,,,,,98

 

you will like the flowmaster 50 on the 4.6, that is what I have. I went out the side, so it may be a little bit louder. When you are idling, you hear a slight rumble, but when WOT you really hear the rumble. Cold weather seams to effect the noise also. Here is a pic of mine,

 

Drove mine from the dealer to the muffler shop, 22 miles on the odometer. DO IT!!!

 

Did mine at around 300 miles. Just hit 40,000 and no issues.

 

Did mine at about 6,000 miles or so. The dealer told me the same story. If they want to guarantee my stock exhaust, they'll find it in my garage attic.