Im buying a new flowmaster muffler super 40 and im curious if jb weld is strong enough to resist the heat from the muffler. IK you can't use it on exhaust manifolds or headers but can you on the muffler, i still have the cats on. I have have a shorty exhaust pipe coming out the side like a ford lightning does.

 

Why o'why, will you be using jb weld on a brand new muffler??

I've never bought jb weld, it's like the duct tape of metal fab... You might as well ask if you can use some bondo with extra hardener in it... Jb weld built itself a great reputation somehow... I for one don't believe in it, there's great glues, epoxies, plastic welding etc that I use... When it comes to metal I use a welder...

Go to a dang shop and have it welded on for $50, better than losing your muffler, shattering someone's bumper cover, or having a family hit a pole trying to avoid your flying debris... paying for that and then a new muffler etc...

 

have it welded or buy quality exhaust clamps. Theres a saying that start with N and ends with rigged. Don't be that guy with a close hanger for exhaust hangers.

 

 

I've never used JB weld, but I prefer to try and use the best possible method if funds allow, and for me that was having a shop weld it. Ford them to cut mine off and weld the new one on with a lot of extra pipe costed me 150.

 

I have some nice clamps and exhaust hangers but i want to use it to plug it up for extra strenght and so there aren't any leaks

 

If you have good clamps you won't need to "plug up" any leaks.
As said though, most muffler shops will weld it for < $50.

 

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If you bring your own pipe. The shop I went to charged about half labor and half for the pipe. That's right, 75 bucks for 10" of 2.5" pipe. They said they had to drive down and get it so they included labor for drive time. To OP, if you do go this rout, bring your own pipe lol.

 

I'd say get a big pack of hubba bubba, gnaw on some for 5 minutes or so, then use that instead. JB weld smells and isn't easy to get off your fingers. Bubble gum is much more pleasant.

 

And this method has a little give when you hit bumps so it'll kinda float where as jb weld wont give and will break from the shock going over a bump