We currently have a flowmaster 40 on our 99 Expedition 4.6L, the highway drone is really getting annoying. Would a 24" glasspack(in place of the flowmaster) cut down on the drone or what are our other options. It is a single stock exhaust w/ flowmaster in place or the stock muffler...

 

The flowmaster 40 does have the loudest drone. The flowmaster 50 has a lot less. I run the Aero Turbine. It has a great sound when on the gas and little to no drone at cruise.

I did read a case on here where the tail pipe was causing a louder than normal drone. Is your tail pipe factory bent or muffler shop bent?

 

its all factory except for the flowmaster....

 

A flowmaster super 40 should have the same sort of sound but less drone inside.

A magnaflow with a large case would probably be good for this application.

 

i've got IMCO's similar sound to flowmasters but drone is not so bad. but if it bothers me i just turn the stereo up