What is everyone’s thoughts on removing the muffler from a 4.0 TJ?
- Thread starter Jharr_02
- Start date
IMO, the only "performance" mufflers out there that don't sound like shit are Magnaflow. I've never had one that's obnoxiously loud, which is odd because you can typically see through them, and they're stainless. I have one on my Jeep only because it was there when I got it, and while it's a bit louder than I'd like, it's not bad enough to prompt me to do anything about it. OEM mufflers are usually nice. Aftermarket stock replacement mufflers, in my experience, usually sound like shit. Pretty much every time I ever need to replace a stock muffler due to damage or rot..which is rare, it gets a magnaflow anymore.
If you want to see how much you'll hate it, pull the post-cat oxygen sensor out and take it for a lap around the block...it'll sound like that but x10.
If you want to see how much you'll hate it, pull the post-cat oxygen sensor out and take it for a lap around the block...it'll sound like that but x10.
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I wouldn't do it, but testing your rig without it is fairly easy to see whether or not you like it. Just be careful where you direct the exhaust if you shorten the pipe - since it can melt bushings, looms, wires, etc.
Airjunky
TJ Enthusiast
I bought my Jeep with a header & old rusty glass pac on it. Then after I rebuilt the engine, I had the muffler replaced with a Flo-Pro. No cat. It sounds pretty good to me. And I'm old. Most people who see the Jeep say it sounds good too.
https://wranglertjforum.com/threads/4-0-engine-knock.21539/page-3#post-414806
The weird thing is while it's kind of loud sitting & idling, it doesn't really get louder as I get going. Which is great. I don't even notice it as I drive down the road.
https://wranglertjforum.com/threads/4-0-engine-knock.21539/page-3#post-414806
The weird thing is while it's kind of loud sitting & idling, it doesn't really get louder as I get going. Which is great. I don't even notice it as I drive down the road.
That's the thing with Jeeps...as you speed up, the tire and wind noise drowns out everything else. LOL.
I've had a few different combo'd exhausts on my Jeep. Best sounding I've had up to this point is a no-brand cheapo shop muffler with the 3rd cat removed.
Grumbles at idle, only hear it inside over the tire noise when I get on it, then it's got a fairly deep no-boom sound to it. Pops and burbles on decel, which I enhanced with some timing adjustments. Can't hear it at highway speed at all, so definitely no drone.
Worst I had was a magnaflow glasspack beside the transfer case to a turndown just before the axle. Sounded like absolute dog shit.
I had a helmholtz resonator style exhaust on my Raptor from Dirty Deeds Industries. Now that was a cool exhaust. I might contact him about making one for the TJ as an experiment.
Grumbles at idle, only hear it inside over the tire noise when I get on it, then it's got a fairly deep no-boom sound to it. Pops and burbles on decel, which I enhanced with some timing adjustments. Can't hear it at highway speed at all, so definitely no drone.
Worst I had was a magnaflow glasspack beside the transfer case to a turndown just before the axle. Sounded like absolute dog shit.
I had a helmholtz resonator style exhaust on my Raptor from Dirty Deeds Industries. Now that was a cool exhaust. I might contact him about making one for the TJ as an experiment.
I shouldn't; Emissions, fuel economy, sound pollution, etc., all considered when designing these vehicles to be "efficient" and compliant to to EPA/Gov. regulations.
Correction, a Jeep 4.0 6 cylinder sounds like shit...
If you've got 1/2 an hour to kill + headphones
https://www.roadandtrack.com/car-culture/g6675/best-sounding-straight-six/
Southtowns27
Member
I have the stainless MBRP cat back system on my 4.0. Louder than stock, but has a lower mellow tone to it. The only way you should run any kind of open exhaust is if your engine compartment looks like this (my CJ)
Shwiftypickle
TJ Enthusiast
i put in a dynomax cat back, i think its the super turbo muffler. not loud at all and sounds great.
Steve Rodgers
TJ Enthusiast
My neighbor has an SE that is fairly well set up, it did the Rubicon a few times. He either has no muffler or some sort of almost muffler. Sounds terrible, drones very loudly, wakes everyone up. The 2.5 needs a muffler, I'm sure the 4.0 does too. Not many vehicles "sound cool" with no muffler, it's just too loud and rough. Even my restored 1973 CB750 Honda has stock mufflers, which in my opinion cannot be improved on. Those stock 4 into 4 pipes have the sweetest rumble.
Sure, the Merlin engines in WWII P51's were unmuffled and have maybe the best sound any engine has ever made but it's a fighter plane.
On road vehicles need mufflers.
Sure, the Merlin engines in WWII P51's were unmuffled and have maybe the best sound any engine has ever made but it's a fighter plane.
On road vehicles need mufflers.
4.0 Jeep. 2JZ Supra...cummins. I beg to differ. Straight sixes sound great.
V8's, I agree. but sound is relative. Ever heard a 2zj without a turbo? They sounds just as good as the turbo engine, just without the spool.
Weary of trying to fit a not fittable muffler around my rear suspension, I fabbed up a tail pipe that runs out the back sans muffling. It is neither annoying or pleasant sounding. It sounds like a TJ with a 4.0 in it and no muffler. But, very few on the trail with have ever noticed. It isn't bad, it isn't good, but it does work.