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fourtenposi
02-10-2013, 13:41
Hey All,

I finally found this rattle in my truck. I have been chasing this thing forever. It turned out that the bracket that bolts to the back of the exhaust manifold that supports the down pipe has a crack in it.

So I am trying to find a replacement bracket and I read that the bracket is no even needed.

What is everyone's take on it? Should I just cut it off and be done, or do I really need to replace that bracket.

Thanks in advance.

DmaxMaverick
02-10-2013, 13:53
Just weld it, in place as it is now (stress relieved). I don't know what they are talking about, but the bracket IS needed. You risk cracking the outlet flange without it.

fourtenposi
02-10-2013, 14:21
Any idea what it is made out of? Its not rusted so I am assuming either stainless or galvinized.

Its maybe got another 1/4 inch before the bracket splits in half.

You can't get at the entire crack so I was debating about pulling it out to get it done. So how much of a PITA are the exhaust manifold bolts? I am really afraid of breaking them off. They are 12 point bolts and they are not rusted so I am assuming that are a higher quality bolt.

More Power
02-10-2013, 17:09
Any idea what it is made out of? Its not rusted so I am assuming either stainless or galvinized.

Its maybe got another 1/4 inch before the bracket splits in half.

You can't get at the entire crack so I was debating about pulling it out to get it done. So how much of a PITA are the exhaust manifold bolts? I am really afraid of breaking them off. They are 12 point bolts and they are not rusted so I am assuming that are a higher quality bolt.

It's stainless. I needed to weld mine a couple or three years ago. We did the welding from beneath the truck with everything in place. If I were ever to remove the downpipe to make a repair, I'd be inclined to use heavier material to help ensure it didn't break again.

Due to rubber mounting, that little welded tab is all that keeps the entire exhaust system aft of the downpipe in position.

rapidoxidationman
02-10-2013, 18:07
speaking only from my own experience, the exhaust manifold bolts are not that bad to take off. Soak 'em well with some PB Blaster and they shouldn't be an issue.

Use some anti seize compound on reassembly.

DmaxMaverick
02-10-2013, 22:43
I've fixed a few of these. It's easy, just lift the fender liner out of the way, and reach in with a MIG. Early models have the bracket welded to the downpipe, while later models have a clamp type bracket. Later models crack much less often, but do on a rare occasion.

I don't recommend removing the broken bracket tab before welding. It's best to weld it in place before removal, or at least tack it and weld it after removal, if removing for other reasons. It's just as simple as that. Welding in place should be a permanent repair, as it's not only being frozen in place in a relieved state, but it also anneals the surrounding metal, making it less likely to crack.

fourtenposi
02-11-2013, 16:39
So you think if I can weld what I can get at it would hold?

Just to clarify, I am talking about the bracket that is bolted to the end of the exhaust manifold, not the tab that is on the down pipe. Mine has the wrap around tab on the downpipe. I guess they fixed the downpipe issue, it just found the next weak link.

I was thinking of a way to support the exhaust in some other way, It just seems to have the exhaust rigidly mounted like that isn't a very good design. You would think there would be a flexible joint somewhere in there.

DmaxMaverick
02-11-2013, 18:07
Ok. That's different. Disregard the above. The typical break in that area is the tab, between the manifold and downpipe. If you can reach the area of the brake, welding may be the best remedy, in any case. That's a judgment call to be made by the person with eyes on it, and who will make the repair.

The reason for the rigid bracket in that area is to protect the downpipe and turbine housing from stress breakage. The rigid connection isn't normally a problem, as the rest of the pipe is rubber supported. Ultimately, one could install a flexible section in the primary pipe (section immediately downstream from the downpipe). If I saw/heard this happening more than a usual one-off situation, with very few repeats, I might be inclined to isolate the pipe in some manner. It just hasn't been that big of an issue.

fourtenposi
02-12-2013, 17:23
I shot a picture and it looks I have more access than I originally through. Do you think welding one side will get it done?

Attached is a picture.

DmaxMaverick
02-12-2013, 20:13
I'd weld it, in a heartbeat. No apprehension. No question about it. A good weld on the one side you can access should be sufficient. If not, it'll just crack again, and you'll only be then where you are now.