Drilling the muffler...? Probably the last thing that I'd recommend. Removing the muffler is a better choice (muffler delete)... if those are your only two options, but why not just install one of the many available aftermarket mufflers?

HP/TQ number are inconsequential with any of the aforementioned mods. If the sound is something you're seeking to improve, then get a good muffler, i.e., Magnaflow, Borla, Flowmaster, etc... or not.

 

I had a 2000 Sport 5.9L with a muffler delete. I didn't know it had a muffler delete until the exhaust fell off one day on the way home from work. Brought it to an exhaust shop and they said I didn't have a muffler nor was there one on there before the pipes fell off. Let me say that thing was LOUD. I could set off car alarms by trouncing on the gas. I don't know what the legality of it is in your area but it is a ticket you are never going to get out of when the cop looks and sees no muffler. Maybe a glass pack? Either way I wouldn't drill your muffler.

 

were there no pipes from the muffler delete back? Or was there a pipe replacing the muffler?

 

(I think Ive posted this in an acceptable subforum since it doesn't pertain to any one particular engine or year, just general stuff. Please move to better subforum if necessary! :smileup: )

Whats your guy's take on drilling holes into the muffler? orrrrrrrr removing the muffler? anything really.

Obviously the correct answer is to buy a new muffler or exhaust parts to make it sound how you want it too, BUT, If you couldn't do that, what do you guys think?

Ive heard that it causes internal rusting in the muffler, or something like that.

Ive also heard that it reduces back pressure resulting in HP loss.

I don't know much when it comes to Exhaust stuff. So school me, guys.

I already know its not a "genius" thing to do, so what makes it so bad?

Thanks!

Internal rusting of the muffler is the result of water becoming trapped inside it's baffles. When you start your engine from cold, moisture vapor forms, condenses and collects as a liquid inside in the muffler until it is burned off. Short trips in cooler weather do the most harm since the muffler never gets hot enough to dry out or the water expelled as vapor along with the other exhaust gasses. Ever noticed the "exhaust steam" coming from the car in front of you on a cold morning? Popular estimates of today claim that it takes up to 15 miles of driving for a muffler to dry thoroughly. Some mufflers, I think, have 'weep holes' to help alleviate this problem.

All internal combustion engines require some amount of back pressure to perform at their best. So unmuffled pipes do nothing for you but make a lot of noise. Stock mufflers for your model are calibrated for optimum performance.

Drilling holes in your muffler, or removing it altogether are the worst choices. So, as an old saying goes,...." Put a muffle on it"

Dancianne

 

Don't waste time trying to drill holes in it. Either remove it and replace it with a piece of pipe, or buy an aftermarket muffler (you can buy a stainless steel straight through muffler for ~$40 IIRC).

 

Remove it if you want...it sounds awesome but very loud. I can feel some bottom end power loss though. This is on a 4.7

 

Drilling the muffler (or knocking the baffles out with a piece of rebar and a hammer) is an old motorcycle trick. Problem is the sound is usually worse than what you had before and performance goes into the toilet. If you are looking for more sound from your exhaust system do it right and get a quality aftermarket muffler. There are a lot of suggestions on this site as to what works.

 

Drilling the muffler (or knocking the baffles out with a piece of rebar and a hammer) is an old motorcycle trick. Problem is the sound is usually worse than what you had before and performance goes into the toilet. If you are looking for more sound from your exhaust system do it right and get a quality aftermarket muffler. There are a lot of suggestions on this site as to what works.

Ran a muffler delete pipe on my 1996, actually improved performance. Dealer told me before I did it that I could delete either the cat of muffler and still have adequate backpressure. Just couldn't do both. The sound in the cab was not bad, but it would rattle windows and set off car alarms.

 

I did it when I was your age... Since cash was tight I decided to drill 1/4' holes in the muffler one at a time until I got the sound just right. Drill a hole... drive around the block- open it up- back home to drill another hole. Repeat until you are happy.

I knew it was dumb and I knew I'd eventually ruin it with rust or whatever but I ran it for two years and was plenty happy with. I knew guys that were spending hundreds ... and mine sounded just as good and sometimes better that my buddies.

I live in California where the weather is friendly but even I knew to drill my holes on the low end to allow moisture to drain.

Have fun!
Oh yeah!... If you drill a few too many holes you can jam little "joints" of tightly wadded steel wool into the holes to make it a step quieter.

 

My actions and thoughts pretty much spot on.

 

Exhaust dumping under the vehicle is a bad idea. My old Gran Torino did that and it gave me headaches in traffic.

 

Ever consider that your headaches were cause by the 1000 other cars dumping exhaust out of their tail pipes in traffic? Just sayin'

 

LOL,been there/done that too as a broke kid many moons ago.:smileup:
The stock muffler is junk as far as flow is concerned and most of the above posters are telling you to throw it away anyways,so why not experiment with it first,bonus is it doesn't cost anything but a little time.
If it doesn't pan out,you still have the option of another muffler or a piece of pipe down the road.

Follow the above advice about starting with only a few holes and adding more if need be,but i'd go for it.

Audio cut his old muffler open now that i think about it,he's got pic's somewhere,but look for a series of spot weld dimples towards the back of the muffler on it's bottom,and maybe drill the holes just before the dimples.
If i remember from Audio's pic's,i think the back wall is nothing more then a resonant chamber (dead air space).
I'll see if i can get him to dig up his pic's,they might help with the hole placement somewhat.

 

I weny to summit racing the other day they had a flowmastetr clone muffler there on sale for 19.50. And other types starting at 20 bucks .
If u take muffler off it will be stupid loud ie attracting unwanted attition from cops

 

When I was researching mufflers I found on pic on here somehwere showing a stock muffler cut open, and was SHCOKED at how restrictive it seemed.
When I removed mine I cut it open to have a look, and it didn't seem AS bad; I've heard the Sport/Laramie may have a different muffler but can't confirm.
Anyway, here she is partially opened up (I ran out of cutting discs, and threw it away after this)

 

from what you all have said, I thinnkkkk I'll wait until I have enough cash to potentially buy a new muffler, but before I do I'll play with it and see if I can get to to sound cool and if I mess it all up Ill just buy a new one. Either way I plan on beefing up the exhaust eventually, so it just has to hold me over until then.

 

FWIW the stock muffler actually flows pretty decent. It seems restrictive but that type of muffler is probably the best flowing for how much noise it muffles. I'd still go with a straight through type any day though.

 

I actually bought my 98 silverado 305 vortec str8 pipe under the cab..it was stupid loud inside and out.. you have to hold off a conversation untill i got up to speed lol. No lie.

I got a 8" cherry bomb glasspack on amazon for 25 bucks and added a tail pipe section from an older truck. Took it to the shop and the welded it all up and installed for 30 bucks. It sound and runs 100x better now and you can carry a conversation. Its still fairly loud but bareable. I like it.

Hope this helps!!

Id try this if your shops have a fair price. I coulda done a turndown for the same price...i have $55 in my whole setup. That includes a ~36" peice of pipe to make up the gap between glasspack and oem pipe, welds, glasspack and all.

 

I havr to agree with giving it a shot, you aren't out anything since you are gunna replace it eventually might as well have fun... I jammed a big concrete chisel thru the outlet of my muffler in my 95 5.2 and it sounded pretty good

 

A old trick of drilling a 3/16 hole in the lowest point in the muffler lets the condensation out and the muffler lasted longer. off subject I know.

KK4

 

A old trick of drilling a 3/16 hole in the lowest point in the muffler lets the condensation out and the muffler lasted longer. off subject I know.

That makes sense, particularly during short drives in cool to cold weather where the muffler and pipes are cold, the water vapor in the exhaust condense on the cold pipes and settles at the lowest point, typically that is the muffler.

So, if you use your vehicle mostly for short duration trips and have no weep hole in your muffler then you run the risk of accelerating corrosion of the muffler.

The weep hole solves this problem.

 

WOOOO GOT IT STARTED

yeah.. I only got it started though... All my bigger drill bits are way to dull and the only small enough one to make pilot holes I could find in the toolbox in my bed broke... Sooo looks like ill be finishing the rest at my fire station tomorrow!

I managed to get one fully done at the tail end of the muffler, I think its around 1/4 in. maybe. Its not too big, but its not small either. And then one little tiny pilot hole.

My friend and I can hear a difference. Its not louder, but definitely has a different tone. We were totally surprised how one hole can change the sound.

 

Since you already know you don't want the stock muffler on there, I see no reason to even think twice about it until you put on a nice system. And for the back pressure, don't go crazy with the holes and you'll probably be just fine. I doubt substantial hp loss, i.e. noticeable will be there.
FWIW though, AutoZone has cherry bombs for like $30.
Also, for fumes under the truck, I cut mine off right behind the rear axle to dump under the box and I love it. Almost complete system, but still nice and trim. Cutting the resonator off (I had an 05, idk if you have a separate resonator or not) gave it a simple couple of dB.

 

I too have it dumped post..I want my peace and quiet during normal driving and hear it when I want to be heard...

 

Buy a glasspack and some clamps. it will cost you less than $100 to replace your muffler and its easy to do yourself. I did mine in about 2 hours. (with a hacksaw mind you). Ideally, you would use an electric saw and have a way to get easy access to your muffler. Good luck and don't drill holes!!! Wait and save some money.

 

Good point, I actually had to use a section of a tailpipe extension because the glasspack is 20" and my muffler is over 23". I cut the extension a bit too short to fit and now I'll have to get another piece to cut to the right length so I can put my tailpipe back on. Guess I'd better do that sooner rather than later.

 

Holes in mufflers

I'll have to admit to my ignorance about this holes in muffler stuff since I won't crawl under a vehicle, nor will shops allow me into their service bay if it's up on a rack for service. In spite of my lack of knowledge, I'd like to comment on the subject anyway:
a. If automotive companies do indeed install mufflers with "weep holes" in their new vehicles, I'd have to wonder why. It seems only logical to me that just about 100 percent of all water and vapor will be either blown out the tailpipe or cooked off inside a hot muffler, even after just a short drive. Now I've seen muffler cut-a-ways as used for demonstration purposes, and it is beyond me to imagine how water trapped between the different chambers inside a muffler is going to somehow manage to escape thru some weep hole in the back end cap. Only a weep hole located beneath each chamber would have a chance of that happening.
b. For those of you who would drill your own holes, my same logic above applies. And anyway how would you know where to drill since you can't see where you are drilling into. Further, I think that most mufflers made today use steel that has a galvanized coating applied to retard rust. If you drill into that metal, you will most assuredly leave holes which have no protective coating around the edge. This would mean that over time, your self made "weep holes" will get bigger and bigger all the while. Do you think this practice will somehow make your muffler(s) last longer? Just seems to me that by drilling holes in your muffler, all you are doing is to create the equivalent of a worn/rusted out muffler which needs to be replaced as soon as possible.
c. Regardless of factory weep holes or self inflected injury, do you enjoy the effects of carbon monoxide? If it's just a little extra noise you want, then go to a good muffler shop, explain that to them and ask for recommendations. I would trust my confidence and health to their professional experience and skill over hauling out my drill and just boring away. As for C-clamping your exhaust system components together, just my opinion, but I'd settle for nothing less than an airtight welded seal at every connection. Isn't that the way Ram and every other car maker does it?

 

alot of car manufacturers do clamp their mufflers on..

 

Hi All,

Let me clarify something here that seems to be getting confused. Drilling out a muffler does not mean poking holes in the outer casing. It means opening holes in the baffle plates. Coming from motorcycles and having done this on several bikes, you need to understand that if you poke holes in the shell or outer case of the muffler you will get a ticket and/or fail inspection. The whole concept is to redirect exhaust gasses around the baffles when they start to restrict back pressure on acceleration. I had a 2003 Triumph Sprint ST that I put a 1" hole into the rear and center baffle plates. It sounded mellow when I was being nice and it definitely got peoples attention when I was being naughty. It also was dynoed and added about 5% because at idle and lower pressures most of the exhaust would still follow the baffles, but when the pressure built up at higher throttle more exhaust would go through the holes that offered less resistance at high flow. It is the shade tree version of flow-through mufflers. Don't know how well poking holes in the case will do, but if it were me I would be drilling a 1-2" hole in the rear baffle plate and see how that works. BTW I did that with a 1" hole saw and two 12" extensions on my Sprint.

Whatever you decide to do good luck and have fun.

preachp

 

then you must mean on a chambered muffler like a flowmaster...it doesn't matter on the straight thru designs like magnaflow..