removing muffler, straight pipe ?

[lunneborgc]

I've ordered the cat delete pipe for the rig and am waiting for it to show up. I primarily ordered it to lower the EGT, and I have been considering getting rid of the muffler as well and keeping the rest of the factory exhaust. I won't be getting a 4 or 5" exhaust any time soon, or doing any other modifications (other than zoodad) I just want to hear the truck a bit more without purchasing an after market system. O.K. on to the question...

While sitting bored at my appt. waiting on the chimney sweepers I decided to see what it takes to separate the factory exhaust at the muffler. After investigation an getting to all the nuts I need to, I basically dropped the exhaust from muffler back, then bolted it back in place next to the existing pipe coming from the Cat.

I did this in my Chevy and drove it for years (with a turn down tube after the cat) but I wanted to make sure there wouldn't be any problems with a diesel running the exhaust that short. It basically ends right after the Crew Cab. I have yet to take it for a test spin, and I just want to get an idea of what it'd sound like without a muffler. I understand I may get an exhaust smell in the cab but I really didn't have a problem with that in the chevy. Opinions?


Thanks yall - Chris

[thbd77]

It will be louder not bad it wont hurt anything to run it that short. Stump has his short on his 04 X in front of the wheels somewhere.

[Mudracer80]

Dont mean to jack your post but I had almost the same question.

How much more will 4" straight pipe lower your EGT's then just removing the muff and cat off your stock system?

[lunneborgc]

From what I've read just removing the CAT will lower the EGT somewhere around 200 degrees. I don't think the muffler being there or not, will have any effect on the EGT.

I just took the truck for a spin, and the only thing that sounds different while driving normal is the exhaust resinating in the cab a bit. Occasionally when driving at low RPM's there's almost a deep whistle, much deeper than the turbo sound. That's gotta be the way the exhaust is exiting the pipe, it could also be making that noise when the exhaust hits the side of the pipe that's supposed to be inside it. With it straight piped out the back of the truck somewhere that should go away. I'm gonna leave it like this for a couple days, see what the ol lady thinks about it (it is her daily driver after all). I still don't have the cat delete on there yet, but don't think it'll make that much of a difference with the sound.

When I get on it, I can certainly tell there's not a muffler, it gives me that nasty diesel grunt we all love so much. I'm pretty sure I'll be going to a muffler shop after I put the cat delete in to get the muffler removed and either keep the pipe out the passenger side rear or have it dumped before the axle. Hell, if I could find a turn down pipe big enough I could just hacksaw the muffler off right next to the weld and do it myself. I looked at the local auto parts store for one with no luck. Thanks for the information thbd77 - Chris