Is It Worth Changing

TONYTHOMAS1956 · July 1, 2011

Is there any real increase in performance or gas milage when you install a different exhaust system? I want one just for the sound but I dont want to go backwards on everything. Was thinking of either muffler only with factory pipes or catback single or catback duels.

Which one would be the best?

ujtruck · July 1, 2011

NO - Don't - unless its fall a part

66and10 · July 1, 2011

What would they be fighting over? Or did you mean "duals."

I seriously doubt that you will see any performance differnce in your seat of the pants dyno. If you want to change the exhaust for the sound, go for it. I put a Dynomax single out cat back on mine, and I love the sound of it.

July 2, 2011

66and10....what part number for that Dynomax catback? Also, any drone on the highway or terrible sound while AFM is kicked in?

GasHog369 · July 2, 2011

With my tune , exhaust , and k&n fipk i saw an increase in mileage of approx 3 mpg... not enough to warrant spending all that $ on 3mpg savings, but it makes it a hell of a lot more fun to drive.

jro909 · July 2, 2011

a different exhuast will do nothing but change the sound on a stock truck...hell it could damage your power and mpg even...i juggled the idea of getting a louder exhaust and after researching it, the price overides the gains

scz71864 · July 2, 2011

if your going to get one dont get a FM, you will lose low end power because of the loss in back pressure

RAF · July 3, 2011

I put a Flowmaster cutback on my truck cuz it was too quiet. Only costed $330 new and I sold my stoker for $100. Install was free because I did it myself. I didn't not notice a difference in power or fuel milage

66and10 · July 4, 2011

66and10....what part number for that Dynomax catback? Also, any drone on the highway or terrible sound while AFM is kicked in?

P/N 39495. Lots more info on my install here:

http://www.gm-trucks.com/forums/index.php?...&hl=dynomax

tyhuck · July 4, 2011

If you want to change the sound, Id suggest running a Magnaflow muffler with the stock tailpipe and dress it up with a polished tip or split tips.

I have put "performance" exhausts systems on many of my trucks, and honestly, I didnt notice any difference in performance. I do think that I lost some low end in my current truck because I went with a 3" tailpipe. I probably should have stuck with a 2.75" or 2.5". Thats why I suggest running the stock tailpipe unless you are running duals. in that case, have a muffler shop suggest a good size for tailpipes. Then if you dont want to do it yourself, just have the muffler shop guys do it. Their system will perform as equally well as one of those high dollar bolt-on cat-back kits. They high dollar kits are tuned, but they really only help if you are running a highly modded motor on the strip, and not so much on a stock DD.

TONYTHOMAS1956 · July 4, 2011

Thanks for all the replies guys. Im thinking Ill just change muffler and keep everything else stock.

BigBlueLB756 · July 4, 2011

How about a Dynomax VT muffler #17957, stainless, 3" inlet and outlet? You'd need a new tailpipe because it's not the same length as the stocker, but it sure would handle any drone issues and sound real good. Summit, Jegs, etc. all have them.

tyhuck · July 4, 2011

All you would need is a small piece of exhaust tubing to patch in behind the aftermarket muffler to fill the difference between the muffler and the stock tailpipe.

TONYTHOMAS1956 · July 4, 2011

All you would need is a small piece of exhaust tubing to patch in behind the aftermarket muffler to fill the difference between the muffler and the stock tailpipe.

What about the "DRONE" going that route?

tyhuck · July 4, 2011

Drone depends on the brand of muffler, length, and position under the cab.

I have a 28" Magnaflow under my truck. Its not as loud as some, but thats what I wanted. It is a quieter muffler so the amount of drone is less. I had a 14" on my old 06 2500 and it would drone quite a bit at certain RPM. It wasnt too bad at cruise speed though. The truck i have now came with a Flowmaster 50 on it with a turndown right off the muffler. It droned rediculously. Dont know if it was the muffler or the turndown or a combination of the two.

Having a tailpipe that exhausts out from under the truck helps out a lot. Most drone comes from sound relection under the truck. Its worse if you dump the tailpipe in the direction of the ground, which causes sound reflection off of the road back to the cab.

IMO, if you want some sound, but dont wnat any drone, go with a longer bodied muffler. Liek I said, mine's a 28" body and its got a rumble slightly louder than a factory muscle car at idle, but it will roar with a nice note under heavy throttle. You may want to look into something around a 20" case or so. Anything shorter will drone more than a longer one.