i have a 2006 dodge ram 4x4 4.7 liter engine.... i currently have a flowmaster 40 series installed with two pipes coming out of that one flowmaster muffler....

do i have any options if i want it to be deeper/louder? more info i have 3 inch pipes.

 

try some hi flow cats like magnaflow, has done the trick for me! I have a 4.7 as well.

 

I dunno if the 4.7 has the same cats as the Hemi, but if you ever check the flow rates of the stock cats vs. the Magnaflows on a Hemi, they are almost identical.

The FM40 is considered a fairly loud muffler so if you want louder, there are not a lot of choices. Cherry Bomb Vortex or Extreme would be a couple of options and would also significantly increase your flow rate as well.

For a deeper tone, nothing I've heard yet compares to a set of LT headers for deepening that note a good bit...

 

dynomax? just got rid of dynomax on mine and went to a larger magnaflow because it was just too loud