Exhaust Repair Basic Question

[WorkinLonghorn]

My '69 with 350 came to me from the original owner in '96 with a custom 2" dual system with no cross-over. It has very long glass pack style mufflers and the pipe to muffler is welded. Exits out the side in front of the rear wheels.
OK, the driver's side muffler is all corroded out. If I cut this junk out then I will probably need to add pipe to make up the difference in length (this thing is huge, like 42"). How do you do that? If I get 2" pipe and some clamps it would seem lame to just butt the sections together and clamp. It would leak. There must be connectors that are slightly larger than 2"? The glass pack mufflers are 2" or are they slightly larger so that you can insert the pipe and clamp? I'm ordering online so I can't see. Anybody have suggestions? MUCH thanks from me and my neighbors. -BA

[Smitty]

By the time you scramble to get everything to make a patch job. The other side will require help. If possible find a good muffler shop and replace the whole system. I had mine done with aluminized pipe with the siamese x pipe 25 years ago. Still in great shape. Just my opinion. Good luck.

[dmjlambert]

In my opinion it is hard to beat a deal from your friendly muffler shop to repair or completely re-do your exhaust. So, have you checked? To find which shop is the best to go to, you have to ask around at auto repair shops, auto parts shops, friends, and nextdoor.com and you might find a good place to go. Then get an estimate for "just the repair" and/or a new exhaust. With that said I have seen exhaust sets sold in catalogs/online (for about the same price a muffler shop charges to just do it), and one of the things sold is a pipe tool that stretches the pipe to be larger around so one pipe fits into another, and you can clamp it or weld it. Also, Auto parts stores such as Auto Zone have loaner pipe tools.

[WorkinLonghorn]

Well, I did take it in to a shop that was recommended and they said something like "$775".

I guess I am way too cheap. I paid $300 for the truck. I see glass packs for ~$40-$80 on Amzn. Unfortunately this is more my style. This is strictly a beast of burden.

That tool that expands the ends sounds like the ticket, thanks, I'll check it out. -BA

[truckster]

Look into something like this. It's already expanded at one end.

https://www.summitracing.com/parts/wlk-41947

[MARKDTN]

You can buy exhaust parts and pieces at the local auto parts store, Summit, Jegs.... You can clamp or weld-but if you have that much problem on 1 pipe now the other will not be far behind. I would pay up and let a shop replace it. Many things I like to do myself, but exhaust is one I farm out.

And those manual pipe expanding tools? Ever try to use one? Not easy, especially if you are able to source some thicker wall pipe. There is a reason that the muffler shops have a hydraulic expander. For 1 end it would be far easier to buy a pipe with one end pre-expanded and cut it to length.

[72SB]

or just get a exhaust manifold back "kit" exhaust system for the truck. I got mine from LMC but it is a 6 cyl. It was around $175. Several exhaust companies (Flowmaster, Pypes, MagnaFlo, etc) make them

Cheapest just fix a section is buying pipe and a pipe expander, or a section of pre expanded pipe on one end, and some clamps

[LS short box]

So I've built a number of exhaust systems for my hot rods. I order a box of bends from Summit. I don't care for glass packs. Way too noisy. I like turbo mufflers. They cut down the sound and are cheap.
So if you are starting with 2" exhaust tubing figure out where the new mufflers are going to go. Get a piece of exhaust tubing (2) long enough to fit inside the inlet of the new muffler and over lap the current exhaust tubing by about 2 inches. Then take those pieces of exhaust tubing to the local muffler shop and have them expand one end of the tubing just enough to slip over the existing tubing. Should cost almost nothing.
Then after expanding slit the new upstream tubing (4 slits) so using a single band clamp will tighten down over the top of existing exhaust tubing.
Do the slit thing to the inlet to the muffler so the single band clamp will tighten on the new tubing.
When assembling use a bit of muffler cement for a great seal. No welding required.
Good luck.

[WorkinLonghorn]

Thanks for all the input and suggestions.
I went with the Thrush 24204 glass pack because I was replacing a glass-pack and that was the easiest route. I spent $49 on Amazon and got the muffler, a section of 2" pipe and the cement suggested by LS Short Box (thank you).
Worked out great. Reasonably quiet (compared to how it was) just required 2 cuts and everything fit just right. I drilled and installed set screws on each joint to add some strength.
The last shop I checked wanted $250 just to replace the muffler so I am ahead and have the satisfaction of doing something reasonably well. Thanks again. -BA

Tomorrow's job is to secure that gas tank in it's correct position above the pipe and also add some support to the front area of the pipe/muffler since it's just baling wire for now.

[54blackhornet]

Baling wire served multiple generations just fine ! Nice work ! I know how you must feel by doing the job yourself…

[HO455]

As usual I'm late to the party but I'll mention using truck clamps since they weren't mentioned earlier.

Truck clamps are 3 inch wide stainless bands that come in most exhaust tubing sizes to clamp and seal two pieces of tubing to each other. I've using them since the mid 90's in place of flanges and collector gaskets.

https://www.napaonline.com/en/p/EXH33226

Photo shows one on my Burban. The Vice Grips are holding the clamp tight as I fabricate the rest of the exhaust pipe. I had to modify the exhaust when I when I moved the crossmember to go from a T400 to a T350. They seal well and are helpful when building your own exhaust from U-bends.

[Ironangel]

Yeah I'm a little late too...Here's the 2" splice sleeves I use when splicing exhaust pipe... https://www.summitracing.com/parts/wlk-41940