I'm sure the truck would benefit from a straight-through muffler, but wouldn't that be a great deat louder inside?
Depends on how much volume it has. And everyone seems to hear differently. I believe they have some that are as long as 30", that'd be pretty quiet, maybe as quiet as oem. Most seem to say the 18" long mufflers or 21" or so one's sound like oem at cruise...