Aint it the truth...when I installed my Gibson cat back when my truck was about a year old, I was expecting a mean musclecar sounding exhaust, but it turned out to be a whisper, and I had just dumped $500+ on it A few years ago when I removed the tail pipes and dumped it before the axle I got the loud rumble that I was looking for. Eventually what's left of the exhaust will be getting removed in lieu of dual 14" long 2.5 in/out round Magnaflows

 

The borla is a very very good sounding muffler. Try taking the front one off and see how it changes the tone.

 

I have never been a fan of Borla. But every one has different taste when it comes to exhaust sound. I like the flowmaster sound first and magnaflow second.

 

so is the powerflo muffler that came on the rst trucks the same as the one that they offer on summit?

 

I just did my exhaust too. True 3" duals no cats. X pipe two borla straight throughs and it is way too loud. My fault for underestimating the flow of the pipe but i gotta get chambered mufflers also.

 

From looking at the pictures of the power flo muffler, I can tell you that wasn't the muffler that came off mine. Mine looked like a flowmaster from the outside.

 

The RST truck originally used corsa, on the NNBS trucks they went with borla. If you had a flowmaster on there, someone swapped it out.

 

if it makes you feel any better, i just added tail pipes to mine after 3.5 years of running straight off the muffler (chambered MellowTone 3" in, dual 2.5" out). i don't know if i like it yet or not. it sounds fine from behind, but i can barely hear it in-cab & have stalled it twice now when backing up. it sounds fine at WOT, but just cruising, it's so quiet i don't know what to do - i ain't got the bed rumbling in my ear no more

 

There you go. The XR-1 is a very good muffler, quite when cruising but really wakes up when you punch it. Get rid of the XS and go from there.

 

quiet is better then too loud... i had a flowmaster 3 chamber and put on lt headers took off cats and thought i wanted more sound so changed it to a supper 44 flowmaster all on 3 inch piping... well guess what.. now the dam truck is louder then ever...in the mrng when cold it makes my windows shake inside my house.. when on the street im too scared to take off in a green light cuz its just loud.. i think its too loud others ask me what i did cuz they love it... for once i would like to have it quiet..lol but goodluck im sure ull get use to the quiet sound.. consider ur truck a sleeper.. not loud and on a turbo.. nice!!!