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Old 01-13-2004, 12:09 PM   #1
KEH
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Should I drill holes in mufflers?

The shop that installed my exhaust mounted my mufflers in the vertical position. I don't know if this is good or bad, but a guy from Midas saw it and said it was stupid. He said they would build condensation and rust out. He told me to drill small drain holes in the low points of the mufflers.

I guess it sounds logical to me. What do you guys think?
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Old 01-13-2004, 12:14 PM   #2
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can you turn them in anyway? sounds like they put the wrong muffler on your truck, or just making sure they get repeat business
If the truck isn't used with a camper or anything so you don't worry about fumes I guess it would be okto drill small holes, just sounds like adding to the problem to me.
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Old 01-13-2004, 12:15 PM   #3
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I have had mufflers mounted like that and never had a problem. I had to mount mine like that because of space and clearance issues. If you drill holes in the mufflers your exhaust will be louder because the exhaust is escaping out the holes you drilled.
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Old 01-13-2004, 01:22 PM   #4
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Most stock mufflers have a small 1/8" hole drilled at the lowest point at one end. It won't make it any louder, but it will be another spot that it will start to rust...
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Old 01-13-2004, 01:29 PM   #5
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Most stock mufflers have a small 1/8" hole drilled at the lowest point at one end. It won't make it any louder, but it will be another spot that it will start to rust...
I THINK I'LL HAVE TO RAISE THE B.S. FLAG ON THIS ONE

NO MUFFLERS THAT I HAVE EVER OWNED HAVE HAD ANY HOLES DRILLED IN THEM TO LET MOISTURE ESCAPE. SOUNDS KINDA LIKE DRILLING HOLES IN THE BOTTOM OF YOUR BOAT TO LET THE WATER OUT. JOHN
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Old 01-13-2004, 01:52 PM   #6
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OK I'M GOING OUT TO DRILL HOLES IN MY BOAT GOOD IDEA
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Old 01-13-2004, 02:12 PM   #7
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If you drive more than 35 miles a day don't worry about it. Most of all mufflers have a aluminized coating on the inside and the outside to help them resist rust. Driving more than 35 miles a day will heat the muffler up enough to evaporate the condensation build up.
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Old 01-13-2004, 02:20 PM   #8
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ok...ok.....ok factory mufflers and alot of aftermarket replacement(stock style) have a small 1/8 inch or so hole at the lowest point in the muffler. to drain condensation out of the muffler. If you drill a small(1/8 inch) hole at the lowest point it will drain condenstion but at the point you drill the edge of the hole will have the aluminization removed and will allow that hole to rust. And true if you drive enough miles at one drive cycle it will help to evap the condensation in the muffler, and the oils and the lubes. short trips are hard on vehicles and will put them into the severe use catagory on most any manufacturers maintence schedules.

Drill if you are worried dont if your not.
your not goung to cause the world to fall off of its axis either way.
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Old 01-13-2004, 02:24 PM   #9
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junkyardjohn........I guarantee that the 84 you own had moisture release holes in the mufflers from the factory

and most boats do have a hole at the lowest point to let water out,,,,,but MOST people plug them before floating their boat.
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Old 01-13-2004, 03:30 PM   #10
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Sounds like advise for the dumb a55 ricers that spend $1000's on a lound exhaust for a civic!
If they were smart enough they would just drill a flippen holes in the stock exaust or muffler!

Don't drill holes man re do it!
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Old 01-13-2004, 03:39 PM   #11
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Re: Should I drill holes in mufflers?

Quote:
Originally posted by KEH
The shop that installed my exhaust mounted my mufflers in the vertical position. I don't know if this is good or bad, but a guy from Midas saw it and said it was stupid. He said they would build condensation and rust out. He told me to drill small drain holes in the low points of the mufflers.

I guess it sounds logical to me. What do you guys think?
And they are not going to condinsate laying flat? I have as yet to see a muffler that doesn't have some sort of lip that is going to preven any water from colecting not to mention most mufflers are mounted before the axle and have to route the pipe up over that.

If you have more then a teaspoon of water collect in your muffler when you shut it down you got a lot bigger problems then condisation. You got a blown head gasket or your truck is in the lake.

Mufflers need some sort of volume to do their job. THe reason they are flat is to alow them to tuck up to the floor of the vehicle. It doesn't really matter what way they mount as far as performance.

As for the condinsation that they do produce. That 500 degree air moving through it will change it to vapor and move it out just like the heat in the crank case does for the condisation in there.
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Old 01-13-2004, 04:47 PM   #12
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Old 01-13-2004, 04:56 PM   #13
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Quote:
Originally posted by Rooster's 67
junkyardjohn........I guarantee that the 84 you own had moisture release holes in the mufflers from the factory

and most boats do have a hole at the lowest point to let water out,,,,,but MOST people plug them before floating their boat.
"MOST" people, hehehe, that was an interesting boat launch....
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Old 01-13-2004, 05:02 PM   #14
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Quote:
Originally posted by Russell


"MOST" people, hehehe, that was an interesting boat launch....
Don't laugh... I did it.. Got 1/2 way across the lake when I noticed the boat wasn't planing to well. Let off the gas and got drilled by 50 gallons of water. Lucky for me my boat is a Direct drive and the plug is installed under the engine right behind the drivers seat. I got a good bath but got the plug in before the boat went under. Bilge pump got a good workout

BTW... I laugh at myself for this one to this day
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Old 01-13-2004, 06:36 PM   #15
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Quote:
Originally posted by Rooster's 67
ok...ok.....ok factory mufflers and alot of aftermarket replacement(stock style) have a small 1/8 inch or so hole at the lowest point in the muffler. to drain condensation out of the muffler.

Mine has holes but I wouldnt say they are drain holes.
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Old 01-14-2004, 12:30 AM   #16
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I have seen plenty of mufflers with the aformentioned drain holes. Both OEm and replacement style. I have never seen them cause any noise either. Not a single one.
If you decide to poke holes in your mufflers, spray a little high temp header paint in the hole. 1200 degree paint should hold up way back there...even 500 degrees amy be a bit high of an estimate.
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Old 01-14-2004, 12:37 AM   #17
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I dont think it is gonna make your mufflers last any longer, mayvbe a year or two more, they'll rust out, eventually, especially if you drive it in the winter, of course the best way is to go stainless steel but it is pricey, unless you work at a mill and get it all for free
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Old 01-14-2004, 12:49 AM   #18
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my 2000 has a hole in it ........weeps water (condensation)
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Old 01-14-2004, 01:44 AM   #19
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Hmmm.. well up here if you want lifetime warranty on your exhaust muffler they center punch a hole in it at the lowest point at rear.. one year warranty = no hole... same muffler either way. Thats what I noticed.
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Old 01-14-2004, 02:18 AM   #20
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Quote:
Originally posted by junkyardjohn
NO MUFFLERS THAT I HAVE EVER OWNED HAVE HAD ANY HOLES DRILLED IN THEM TO LET MOISTURE ESCAPE. ....
OK, Ill be specific then. NO the holes aren't "drilled" in them, they are punched or stamped in them.

Do us favor and go look at a few stock mufflers before you call my response bullsh!t. Do us another favor and turn YOUR CAP LOCK OFF

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Old 01-14-2004, 02:24 AM   #21
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Anybody ever hear a ford exploder with the stock steel muffler? Drain holes right in the middle. After it rusts a bit they tend to make a whistling noise. I've had many people come in wondering whats wrong with their ford.
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Old 01-14-2004, 03:46 AM   #22
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it's a ford ding-dangit!! god this is a funny thread!!!
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Old 01-14-2004, 07:59 AM   #23
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Quote:
Originally posted by N2TRUX
OK, Ill be specific then. NO the holes aren't "drilled" in them, they are punched or stamped in them.

Do us favor and go look at a few stock mufflers before you call my response bullsh!t. Do us another favor and turn YOUR CAP LOCK OFF

NUTUTRUX. HMMMMM -- I CRAWLED UNDER ALL 8 OF MY TRUCKS..... & NOT A SINGLE DRAIN HOLE TO BE FOUND IN ANY OF THEM (& MOST HAVE 2 MUFFLERS) BUT MY NEWEST TRUCK IS 22 YEARS OLD, & THEY'RE ALL CHEVYs OR GMCs. I ALSO HAVE 4 BRAND NEW IN THE BOX FLOWMASTER 40s SITTING HERE WITHOUT ANY DRAIN HOLES. ALSO A PAIR OF HOOKER AERO CHAMBERS & NO HOLES. MAYBE IT'S A RECENT THING, OR JUST ON DODGES & FORDS??
AS FAR AS ME TYPING IN ALL CAPS (NOT THAT I FEEL THE NEED TO EXPLAIN MYSELF TO YOU) I'M HANDICAPPED & ONLY TYPE WITH ONE FINGER ON MY LEFT HAND, & FIND IT A REAL PITA TO SWITCH FROM LOWER CASE TO UPPER CASE ALL THE TIME. IF IT BOTHERS YOU TERRIBLY..... PLEASE PUT ME ON YOUR IGNORE LIST(IT'S UNDER USER CP) & MY POSTS OR REPLYS WONT SHOW UP TO YOU.
DRIILING HOLES IN YOUR MUFFLER (& BY ALL MEANS DO IT) SEEMS LIKE TAKING A BATH WITH YOUR SOCKS ON TO ME. OUT HERE EXHAUST SYSTEMS LAST 8 - 10 YEARS AS COMPARED TO 2 YEARS WHEN I LIVED BACK IN MICHIGAN.
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Old 01-14-2004, 11:48 AM   #24
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And to think I spend hours trying to seal up holes in my exhaust with a welder---only to find out I should be making holes!? Actually I have done the hole thing and am not sure that it really makes a big difference as mufflers are internally designed to muffle---and are NOT designed to drain condensation to any pre determined spot so you will probably be doing a superficial thing with drilling a hole for the lowest point. Condensation will still collect water within the baffles that gravity will not drain.
My personal preference is to leave the SOB alone as after a while I kind of want a change of tone and another muffler anway. AND I don't want to hear a cherp,peep,sush,pop etc. from the exhaust that I caused. I got enough from my crappy welding already!!
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Old 01-14-2004, 11:54 AM   #25
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Naaa, your post don't really bother me with the cap lock thing. At least now I know why. Normally I find your responses very informative and polite. That's why I was surprised when you got on my reply as bullsh!t that way.

I do have a lot of late model stuff, but I can vouch for at least one older GM vehicle haveing the hole in a stock muffler. The first time I saw the drain hole in question was on my 84 Z-28. It had one in the factory muffler and it always puked black carbon crap across the muffler.

I know my 95 and 97 Silverado had the same hole in itheir muffler too...

BTW- I'm not handicapped and I only use two fingers to type
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