Front end noise when hitting bumps (sounds like metal slinky)

So, I recently replaced my head gasket on my 4.0 and on my first test drive after doing the job, I hit a bump going about 25mph and it made a noise like something scraped or came loose (that might be because the “hood prop” [or whatever you call it] came loose). Ever since then, if I go over a bump I hear a noise coming from the front end that I can only describe as sounding like one of those metal slinkys, but the noise only lasts for a split second. Just about every bump i hit when going at city speeds (15-35mph) I hear the noise and I just can’t seem to narrow it down.

so far, I have checked u joints, sway bar connects, track bar, control arms, shock mounts, and the exhaust pipe to see if it was rattling against something. Does anybody else have any ideas?

 

When was the last time you changed shocks and what kind?

 

I’ve had the Jeep for a year and a half, it had a brand new lift kit on it when I got it. I have no clue what brand they are if that’s what you’re asking. They are all silver so maybe rubicon express.

 

Noise while encountering bumps make me consider worn suspension bushings or CAT shields or exhaust movement. Inspect/remove the shocks if you don’t know their history as shock bushings can wear funny or shock damage from overextension is also possible.

 

Ok, just took a three hour trip down to the coast and didn’t encounter the slinky sound, but when I got down here I heard a metallic rattle when crawling to a stop that sounded like the heat shield plate. I’ll check it tomorrow and see what I find.

 

After a couple of weeks of hearing these noises, I think the two might be connected but I have checked every suspension part in the front and didn’t find anything. Then I tried checking out the noise that sounded like the heat shield. After removing the heat shield I still heard it so I banged on the exhaust with my fist and heard the same noise coming from the muffler. So, I think I need a new muffler. Does anyone agree, or should I keep checking?

 

Sounds like you found it.
BUT I think you need to keep checking

 

To bang on the exhaust to locate the "metal slinky" noise is good but signs of mufflers failure are usually louder, leaky, rusted or falling off. Check the rest of the exhaust system for looseness or defects such as the heat shields, heat expansion bolts (ones with springs) etc.

 

The muffler is a little “leaky”, I have seen several places on the muffler that look wet and I have seen water dripping out of it before. Not sure if that’s what you were talking about or if it’s something I shouldn’t be worried about. As for the looseness and defects you were talking about, I haven’t spotted anything, just the rattling muffler.

 

Was referring to exhaust leaks. Some mufflers are designed to release excess moisture. If the muffler is rattling get it replaced or wait till it gets worse.

 

i know you were talking about exhaust leaks. When I posted that it was late at night and was probably tired and not thinking straight. Anyway, I have already ordered a muffler. I tried to get OEM muffler from a Jeep dealer but they said it was discontinued. I found a website that had Mopar parts but they charged WAY too much for shipping so I ended up getting a Flowmaster super flow 44. The reviews on it were good so I’ll see how it goes.