Got a muffler installed yesterday and went with the Flowmaster Super 40. The guys at the shop (two shops) said it is, as far as loud, is between the 50 and original 40, with the original 40 being the loudest and the 50 not being much more than stock. I like it so far. It has a nice low rumble to it at idle (not loud, just deep). It's loudest when you're on the gas. When you're off the gas you cannot hear it at all. When running 60-70mph, it's pretty mild. When you run 50mph it sounds like you're idling...
It sounds best right off idle through 2000rpms. It does have a drone at 1800rpms when barely on the throttle.
I had it next to a friends 99 taco this morning with a glasspack and the 40 sounded a lot deeper and wasn't as loud as the glasspack. The 40 was a lot mellower and deep. On WOT, the engine noise takes over, and I'm not quite sure how it sounds outside.
All in all, it sounds like a V6 with a muffler. But at off-idle to 2000rpms, it's best... nice and gurgly.

http://www.flowmastermufflers.com/40_super.html

 

Good review. Are you still running it? Do you still like it?

 

Love it, not too loud, not too quiet. I would go with the Super 40 (not the original). I think the original is louder but the Super is really deep sounding

 

nice.... i wish i could put one on the 4runner im driving

 

got any sound clips or is the clip on the flowmaster website pretty close to the actual sound?
i'm thinking about going with one myself or the 50 series.

 

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