Had way too much cab drone at 2k rpm. 21" magnaflow, custom Y dual 3" out the back. Put a small, straight through muffler in just before the Magnaflow to act as a res. Didnt have a res on hand at the moment. Worked out great. No drone, alot quieter all around. I dont have an exhaust for the sound, just performance. I didnt lose any performance. Win win for me. Truck is an 05, 5.7.

 

Tips exit behind rear wheels, not out the back.

 

Did you notice ANY performance from the Magnaflow?

 

I initially just did the exhaust and it alone made a difference in mpg slightly. Performance wise I noticed after the Flashpaq. I cant say if the exhaust alone did much because it may be in my head. Im told the Magnaflow was the right way to go.