Muffler Info

Everything to do with engines, options, upgrades.
Post Reply
pushx
**Forum Contributor**
Posts: 40
Joined: August 14th, 2017, 8:49 am

Muffler Info

Post by pushx »

I have a 1989 Ford 350-based Chinook (7.5l v8) and its got a big hole in its muffler. The info I have is confusing so maybe somebody here might have more details.

The broken muffler is 30" long with a single pipe in and a single pipe out. When I look online for the 7.5l engine the mufflers are 25" long and have a single pipe in and two pipes out.

http://www.autozone.com/emission-contro ... 6666_25138

I'm wondering if this muffler broke because the previous owner put the wrong muffler on it. The 5.8L engine muffler is about 28" and same diameter:

http://www.autozone.com/emission-contro ... 8670_25138

Can anybody tell me if they have a similar setup and how it works for them? Does this really even matter and I can just throw the 28" muffler on there?

Thanks!
1989 Chinook Concourse
Tucson, AZ
User avatar
Scott
**Forum Contributor**
Posts: 608
Joined: October 12th, 2015, 5:54 am
Location: Santa Cruz

Re: Muffler Info

Post by Scott »

My original was 1 in, 2 out. I changed it out for a single in/out. I put a monster in there because I wanted as much flow as possible with the least amount of noise, and I already had the whole exhaust out. After the catalytic converter, you can do whatever you want. Just take it to a reputable shop and tell them what you're looking for. Depending on your location, you can probably get a muffler, a new tail section, etc. installed for about $300; of course first make sure they can lift your rig ;) . If you need more information, I can probably dig up the part number for the unit I installed (it's nothing exotic).
1994 Premier
pushx
**Forum Contributor**
Posts: 40
Joined: August 14th, 2017, 8:49 am

Re: Muffler Info

Post by pushx »

Thanks for the info Scott! I've looked at it and decided I'll have a muffler shop do it since it's probably dead simple for them, like you mentioned!
1989 Chinook Concourse
Tucson, AZ
pushx
**Forum Contributor**
Posts: 40
Joined: August 14th, 2017, 8:49 am

Re: Muffler Info

Post by pushx »

I bought the single-pipe muffler #18378 and took it to a muffler shop here in Tucson. $60 muffler + $60 install, done in an hour, not bad. HUGE difference in noise and seems a bit peppier! Hopefully a hole doesn't blow in this one as well.

Perhaps this will help someone out there:

tl;dr: Don't trust the outlet stamp on your muffler! Confirm the inlet/outlet best you can.

So the one weird thing about this was that the mechanic showed me that the muffler I bought had the 'outlet' stamp in the opposite direction of my current muffler. Now I was thinking about putting this on myself yesterday so I'd looked up the input/output direction online and I was positive that the outlet was marked wrong. But here's a mechanic who knows his stuff, and I'm just some guy. We looked it up online together, he felt comfortable putting it on with the 'outlet' stamped side on the inlet. It looks weird when I peek at it under the van now!

I go get a coffee and I just start sweating about this. I could be very wrong! I pull out the computer and find 3 websites listing the part with the inlet pipe 'centered' and the outlet pipe 'offset'. My muffler has the outlet pipe 'centered' and the inlet pipe 'offset'. It has the same model number stamped on it, 18378 , like in the picture, but on the wrong side!

I find Walker Exhaust's phone # and call them. I explain that I think the stamp's on the wrong side and he's like 'oh yeah, it probably is.' Apparently this happens all the time when they make the things and put the sheeting on upside down! Props to Walker for the phone support, but ding 'em a star for putting the outlet stamp on the wrong side of a non-reversible muffler!
1989 Chinook Concourse
Tucson, AZ
chin_k
**Forum Contributor**
Posts: 2257
Joined: June 26th, 2017, 9:38 pm
Location: Southern CA

Re: Muffler Info

Post by chin_k »

I don't know what yours looks like, but it usually take a bit more than just put the sheet on the cutter up side down to make the stamps to appear on the wrong place. But whatever, glad that you got it all worked out.
2000 Concourse dinette, on 1999 6.8L Ford E350 Triton V-10 Chassis
Post Reply