I recently purchased a '10 XLT with the 4.6 3V. I read and read here and on the other F150 forum on adding some sound to my truck and I concluded adding a 12" 2.5"diameter Dynomax bullet to the stock system would be a safe and relatively inexpensive way to do this.I contacted a good friend that installs exhausts and he stated that Ford engines like backpressure and the bullet would indeed increase sound but would kill some performance. I greatly value his opinion on this but I would like different thoughts on this.Help me out,please !

 

It should be fine... staying at 2.5" helps with that small of a muffler.

 

i have actually had this happen on Dodge trucks before. i installed a single glasspack on one, which is basically the same thing as a Bullet muffler just cheaper, and i lost some significant power. i could honestly feel the truck was weaker. as soon as i took it off and put on a super turbo muffler, the power was back and the truck ran great. it didn't sound as good, but it ran 100 times better. just get a Magnaflow or Dynomax turbo style muffler. this will give you the sound you are looking for and still have plenty of power.