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BlackRubi
October 26th, 2010, 11:12 AM
So, I've been noticing a "thud" type sound whenever I hit a dip in the road or brake hard. I attibuted this to the loose bolt on my skidplate (still have yet to get it fixed). The other day, I crawled underneath the Jeep and noticed some wear on the outside of the U-joint on the front driveshaft. Upon closer inspection, I noticed that the driveshaft seems to be hitting the exhaust header, and denting it to make a home for itself. Has anyone had this issue before. I can't really spring for an aftermarket exhaust and I don't even know if that would help. Would an exhaust shop be able to fix the issue? Maybe reroute or adjust where the header sits? If so, does anyone know of a good exhaust shop that won't kill my wallet? Thanks for the help!

southpaws3
October 26th, 2010, 11:46 AM
AA performance SCOTT 3038068634 3898s broadway tell him fr4x4 sent you

Robert B
October 26th, 2010, 12:32 PM
i dont know where to go but if it is hitting the header it self not just the exhaust tube then most vehicles i have seen they had to get a new header and get the tube rerouted to the back of the new header ..... althogh if its a long header they might be able to bend it some .... just what i have seen before and i dont know much about jeeps though :) luck in fixing it

Chris
October 26th, 2010, 12:48 PM
AA performance SCOTT 3038068634 3898s broadway tell him fr4x4 sent you

X2!

Mporter
October 26th, 2010, 02:00 PM
AA performance SCOTT 3038068634 3898s broadway tell him fr4x4 sent you

X3 and let me add one for Pete as well
X4

Brody
October 26th, 2010, 02:41 PM
X whatever for AA. Scotty is really good and knows his stuff, stock, racing, ATV, dragsters, sports cars, 4x4s, etc.

When you say "exhaust header" do you mean the section just below the factory manifold where the collectors are? Or is it hitting the actual manifold? Or do you actually have an after market header? One thing you can do that won't affect too much and is dirt cheap, is to just extend the existing bump stops down 1/4-1/2" by using a piece of steel plate (or aluminum), washers or whatever else seems to be handy (except a chunk of wood...). Chances are the reason that you are now noticing it is because the once new springs are sagging just a little bit. The only wheel travel you will loose will be some up travel which you probably won't even notice. Not a permanent fix, but should get you by for quite awhile.

I had the same problem on the Yota and did this about two years or more ago. I left the dent in the driveshaft as it was, and between the extended bump stop and the dent, it hasn't hit it since....

scout man
October 26th, 2010, 05:14 PM
what everyone else said - but I will add. I would suggest checking all the exhaust hangers to make sure they are all still intact, and check your engine mounts to make sure it isnt the engine that is out of place. This is unlikely, but a good time to check anyways. Never know if the contact being made is a symptom instead of a problem. The exhaust hangers being worn or ripped are probably far more likely than the engine mounts though.

Brody
October 27th, 2010, 05:35 AM
Thanks Steve for that! I have fixed broken exhaust hangers/rattles on five different rigs this year, so you would have thought I would have mentioned that....

X2 on the motor mounts. Something on the basic geometry has changed. I mentioned the springs losing some arch, Steve mentioned a broken/loose motor mount. The motor mount is certainly easier to check. Speaking of "stuff"..T case mounts may be worn to the point where stuff has settled or shifted.

This kinda junk starts happening, it is a good reason to put on the grubbies, grab some safety glasses, a bucket of quarters, cans of degreaser, and clean off the whole underside of the heap....

BlackRubi
October 27th, 2010, 08:45 AM
The T-case does attach to the skidplate (loose bolt). But I would think that would lower the DS away from the exhaust. It's the downpipe after the header. Everything is stock, so it's probably something simple (hopefully).