Off the shelf muffler options..

[Humpty]

My M998A1 has a straight pipe from the headers to a glass pack for an exhaust tip. It’s super loud and I thought it was just part of the Humvee experience till recently I heard how it’s *supposed* to sound with the stock muffler.

Rather than fork over big money for a new replacement part number muffler I thought i’d see if anyone had used something more .. common. Maybe a muffler from a civilian 6.2 from the same era?

 

[DREDnot]

I would suggest Asking around for a stock take off system off someone's parts truck. Maybe post up a WTB ad in the classified section. Unless you got a decent custom muffler shop locally that can fab up something for you

 

[Mogman]

I have never seen anything like this on a civy truck

 

[Vapor Trail]

i have one for sale. looks to be in good shape from the outside. PM me if interested, I can put on a pallet and ship it. Not sure what its worth

 

[Humpty]

I have never seen anything like this on a civy truck
View attachment 907998

I get that there aren’t a lot of mufflers that look like *that* but all I really need is a muffler that’ll fit in this spot where the original muffler would have been.

 

[Mogman]

I get that there aren’t a lot of mufflers that look like *that* but all I really need is a muffler that’ll fit in this spot where the original muffler would have been.

It would be best just to get a real one, not many mufflers have the outlet at 90deg and that is not the only thing that makes it fit, plenty of used ones out there.
I suppose you could jury rig something like the last owner did, then the next guy can feel the same way you feel about him.

 

[Humpty]

It would be best just to get a real one, not many mufflers have the outlet at 90deg and that is not the only thing that makes it fit, plenty of used ones out there.
I suppose you could jury rig something like the last owner did, then the next guy can feel the same way you feel about him.

For starters, "what's best" for anyone is up to the individual to decide.

Second, I just painted this mofo with Caterpillar yellow tractor paint in my driveway. The likelihood I give a wet, corn riddled fart about how the next owner of this truck feels about me when I'm dead and gone is zero. With that said, I have no ill will or feelings toward the previous owner. The original muffler was likely roached and they (like me) decided they weren't going to pay a kings ransom plus a left testicle for a muffler just because it is associated with a "humvee" like every other nut and bolt on this thing. The previous owner just slapped in a hunk of straight pipe and put a glass pack on and called it a day. Functional, but only a shade better than a straight exhaust as the amplitude is roughly that of a small helicopter lifting off when you accelerate from a dead stop.

Sure, there are plenty of used ones out there. What are they replacing them with? A fellow kindly offered to sell me his used one in this very thread. Talkin' about strapping it to a crate. The shipping alone would likely be more than I was interested in spending all together.

It's a rudimentary Diesel engine, not a rocket ship. I find it impossible to believe there isn't an off the shelf Auto Zone muffler that would fit in that spot and perform as well or better than the OEM unit. I just thought I'd check here to see if anyone had done so and save myself some legwork.

 

[Vapor Trail]

Personally I’m replacing mine with a 39” Borla from a trophy truck but now I see why you never responded hahaha

 

[DREDnot]

Most used takeouts ive seen are from parts trucks so no intel on replacement available. Those that do replace theirs are ending up wanting more sound and spending decent money for the upgrade. They are made out of stainless steel so they never just rust away and need affordable replacements.
If you want to replace that cobble you have on a budget will require YOU to get under there and remove that masterpiece and take measurements and then go to muffler manufacturer websites and look up the specs for something that might get you where you want to be.

There is nothing cheap in the HMMWV world and shipping HMMWV parts is always expensive.

The best thing to do (if you don't want to fab/research it yourself) would be to have a competent muffler shop handle it. But being in SoDak you may not be close to one.

Maybe try looking on a civilian H1 forum as you might have better luck finding exhaust mods than on this forum that is more military spec related.

 

[royg]

For starters, "what's best" for anyone is up to the individual to decide.

Second, I just painted this mofo with Caterpillar yellow tractor paint in my driveway. The likelihood I give a wet, corn riddled fart about how the next owner of this truck feels about me when I'm dead and gone is zero. With that said, I have no ill will or feelings toward the previous owner. The original muffler was likely roached and they (like me) decided they weren't going to pay a kings ransom plus a left testicle for a muffler just because it is associated with a "humvee" like every other nut and bolt on this thing. The previous owner just slapped in a hunk of straight pipe and put a glass pack on and called it a day. Functional, but only a shade better than a straight exhaust as the amplitude is roughly that of a small helicopter lifting off when you accelerate from a dead stop.

Sure, there are plenty of used ones out there. What are they replacing them with? A fellow kindly offered to sell me his used one in this very thread. Talkin' about strapping it to a crate. The shipping alone would likely be more than I was interested in spending all together.

It's a rudimentary Diesel engine, not a rocket ship. I find it impossible to believe there isn't an off the shelf Auto Zone muffler that would fit in that spot and perform as well or better than the OEM unit. I just thought I'd check here to see if anyone had done so and save myself some legwork.

Dearest Humpty:
If you spend time reading this forum you will find many exceptional people who have considerable expertise and wisdom, but also kindness to help others with their problems. The two people I most respect in this regard are Retired War Horses and Mogman. RWH because his knowledge on these trucks is simply unparalleled and Mogman because he generously tries to help everyone.

Mogman has given you good advice. You don't realize it's good advice but it is. There are no aftermarket hmmwv exhaust systems for cheap with free shipping. There aren't any easy/peasy civy muffler swaps from 97 silverados. You can of course build custom anything. You can spend your time and money reinventing the wheel. If you had the fabrication/welding skills to do so I doubt you would be here asking. There are lots of used takeoffs. There are deals to be had. The hmmwv exhaust is very well engineered. That is why what Mogman suggests is indeed the best solution. You're clearly NOT looking for the BEST solution- you're looking for duct tape and bailing wire solution. But don't you already own that?

Best of luck finding a replacement at autozone that works as well or better. Be sure to share with us the part number.

 

[Humpty]

Dearest Humpty:
If you spend time reading this forum you will find many exceptional people who have considerable expertise and wisdom, but also kindness to help others with their problems. The two people I most respect in this regard are Retired War Horses and Mogman. RWH because his knowledge on these trucks is simply unparalleled and Mogman because he generously tries to help everyone.

Mogman has given you good advice. You don't realize it's good advice but it is. There are no aftermarket hmmwv exhaust systems for cheap with free shipping. There aren't any easy/peasy civy muffler swaps from 97 silverados. You can of course build custom anything. You can spend your time and money reinventing the wheel. If you had the fabrication/welding skills to do so I doubt you would be here asking. There are lots of used takeoffs. There are deals to be had. The hmmwv exhaust is very well engineered. That is why what Mogman suggests is indeed the best solution. You're clearly NOT looking for the BEST solution- you're looking for duct tape and bailing wire solution. But don't you already own that?

Best of luck finding a replacement at autozone that works as well or better. Be sure to share with us the part number.

It is a rudimentary diesel engine. The factory muffler is gone and replaced with straight pipe. Probably not DOD regulation straight pipe. It has a glass pack on it. Also not likely a DOD regulation glasspack. Guess what? It runs great. Just loud. What sort of magic do you suppose happens inside a muffler? You get one with the proper inlet and outlet diameter that fits in the space. Again, not rocket science. It seems folks around here have little stomach for deviating from the technical manuals. I’ll be sure and share the part number and link when I find one so if anyone else has the same question they’ll get an answer rather than “don’t do it.”

 

[Humpty]

I started this thread asking if anyone had used an aftermarket muffler on a humvee because my current exhaust is a straight pipe with a glass pack as an exhaust tip. Folks here act like aftermarket automotive parts don’t exist, or that if it doesn’t specifically say “humvee” that it can’t possibly work.

As exhibited in my photos earlier and reposted here with a highlight, simply bolting in a stock exhaust isn’t an option. The flange where the original exhaust attached has been removed and a hunk of 3” pipe welded in. To return this vehicle to stock, i’d have to either replace the entire exhaust system or cut out the welded in pipe and weld in a flange. Easiest, least expensive, and absolutely proper course of action from a functionality standpoint would be just to install a off the shelf muffler in place of the current straight pipe (that’s that’s currently bolted in with lap joint clamps)

Lots of guys like to keep these things bone stock and i’m of the opinion it’s your truck, do what you like. Parts availability for these things based on “official” part numbers can make that a pricy proposition. There are also lota of guys buying these trucks (like myself) that respect the heritage but also want to keep them on the road without selling a kidney to do so.

$41.99 for a Thrush muffler with 3” inlet and outlet.. and free shipping. Hot rod and performance guys as well as shade tree mechanics have been hanging their own exhaust for years. I only poised the original question because I thought surely someone had used something besides a $700 used, stock muffler on their truck before now.. especially since these things are essentially just glorified farm tractors.

Allow me to be the first.

 

[TNDRIVER]

I started this thread asking if anyone had used an aftermarket muffler on a humvee because my current exhaust is a straight pipe with a glass pack as an exhaust tip. Folks here act like aftermarket automotive parts don’t exist, or that if it doesn’t specifically say “humvee” that it can’t possibly work.

As exhibited in my photos earlier and reposted here with a highlight, simply bolting in a stock exhaust isn’t an option. The flange where the original exhaust attached has been removed and a hunk of 3” pipe welded in. To return this vehicle to stock, i’d have to either replace the entire exhaust system or cut out the welded in pipe and weld in a flange. Easiest, least expensive, and absolutely proper course of action from a functionality standpoint would be just to install a off the shelf muffler in place of the current straight pipe (that’s that’s currently bolted in with lap joint clamps)

Lots of guys like to keep these things bone stock and i’m of the opinion it’s your truck, do what you like. Parts availability for these things based on “official” part numbers can make that a pricy proposition. There are also lota of guys buying these trucks (like myself) that respect the heritage but also want to keep them on the road without selling a kidney to do so.

$41.99 for a Thrush muffler with 3” inlet and outlet.. and free shipping. Hot rod and performance guys as well as shade tree mechanics have been hanging their own exhaust for years. I only poised the original question because I thought surely someone had used something besides a $700 used, stock muffler on their truck before now.. especially since these things are essentially just glorified farm tractors.

Allow me to be the first.

Don't forget the pics when you get it in. And there are several things on these when they break, well, you will be just fine with one kidney.

 

[TOBASH]

I decided to just use a USMC exhaust on my Whipple supercharged Hummer. Gonna install this weekend. I’ll post results. Same 6.5 engine and frame and body BUT civilian electrics.

 

[Humpty]

Don't forget the pics when you get it in. And there are several things on these when they break, well, you will be just fine with one kidney.

It'll be here Wednesday.. so I'll post photos by the end of the week.

No question there are things that when they break, you gotta buy the right part. That's with everything. Other things.. like fuel injectors, for instance, I have my 6.2 running like a swiss watch on off the shelf injectors for a civilian 6.2. The "Hummer" mirrors are $160 plus shipping everywhere but are identical to the Jeep TJ mirrors you can bag for $40 and free shipping. The notion that every nut and bolt on this thing has to have a specific part number on it to work properly is flawed.

 

[Humpty]

I decided to just use a USMC exhaust on my Whipple supercharged Hummer. Gonna install this weekend. I’ll post results. Same 6.5 engine and frame and body BUT civilian electrics.

Hard to tell if that’s sarcasm or not.. but seems like if you’re putting more air in you’d want to make accommodations for more air *out* as well. It certainly would work but might negate the advantages of the supercharger if it pushed more air than a military 6.5 turbo.