massarosareloud

Hi everyone, I have a 1996 Jeep Grand Cherokee limited edition that I just purchased. In case anyone is wondering, it's a I6, 4L, with 104k miles. Paid $3200.

Unfortunately as I am now realizing, there are a myriad of very small problems that I have to work out. Besides the minor ones (new air filter, oil leak, alignment...), it seems there is some rattling sounds from the back end of the car. Here is my most detailed description of when this occurs, when I switch the car out of park, into drive, with my foot on the brake, and the car is not moving at all, there is a rattling sound from the right hand side of the car, near the back wheel. I've taken some pictures to aid in my description, and I'd love for someone to weigh in on what they see in the pictures that seems amiss.

My first instinct with the rattling is a loose or broken exhaust pipe hanger, but now I am also considering that the catalytic converter may be damaged (ceramic all broken up). But I've read that it could be the heat shield as well.



^^^Looks like the exhaust pipe was patched.



^^^Does this mount look like it is correctly installed?



^^^Now this is what I think is causing the noise, the exhaust pipe is resting on that piece of black suspension, and I can lift the exhaust pipe and let it drop down onto the black suspension piece. Seems like that would cause the sound... Also what is that rusted oval, near the spring?

Bustedback

It does look like the pipe is hitting the sway bar.

71chevytruckguy

Looks like the pipe is hitting the track bar.

Bustedback

You're right, that is the track bar.

massarosareloud

Ok, great! Thanks both of you! I'm going to take a wire coat hanger and see if I can remove the problem by raising the exhaust pipe. What should be my permanent solution? Unless the coat hanger idea is sufficient for long term use.

dave1123

I had the same problem on my 97 ZJ with a brand new tailpipe. What we did was cut the hanger wire with a sawzall, overlap the pieces and welding them back together, thus shortening the hanger. Just remember to disconnect the battery ground before doing ANY welding on the vehicle!

I also added a hanger behind the muffler by drilling a hole in the floor. I felt the system needed more support for the cat and muffler. When I bought it, it had no tailpipe and the cat was cracked because it wasn't supported at all.

massarosareloud

Unfortunately I did not get the wire coat hanger in place because we got a few inches of snow today, and I was not too excited to lay in the snow to work on the car. But I plan to tomorrow! And I don't know how to weld, so I think I am going to stick with the Macgyver solution until I can, at the very least, narrow the problem down to the tailpipe, and rule out the catalytic converter.

Bustedback

A muffler shop would only charge you a few bucks to fix that.

dave1123

Heck, a good ol' boy garage would do it! Probably for a 6-pack!

massarosareloud

Ok, that sounds like a sweet deal, I'll make some calls and see what I can do. Thanks!

Bustedback

You might have better luck by going to the muffler shop and showing them whats going on. Might save you a few bucks instead of getting a quote for an hours worth of work and it only take 10 minutes to fix.

dave1123

My suggestion was only from past experience. I found a shop run by a couple of old hot rodders and classic car guys. They cut and welded my hanger in about 10 minutes and said "I'll have to charge you $10." I gave them $25 and sat and had a couple of cups of coffee, shot the breeze for another hour. Of course, I'm 67 and they were also.

Building a relationship is priceless!

massarosareloud

Well that won't be nessecary, I had a breakthrough today while trying to figure out what I was going to do. I happened to go in my basement and noticed the wastewater pipes hanging apparatus. And so 20 minutes later this happened!!! The rattling sound is almost completely gone, it still rears its ugly head when the car is in reverse, but it isn't nearly as bad. The mount is actually causing the problem because I can't raise up the muffler any higher, which would solve the problem, but I am satisfied as it is right now.

dave1123

Just something I've done before that I'd like to pass on. I've used chunks of 2x4 to support the muffler and a hydraulic jack to bend the pipe on my Chevy truck to eliminate a rattle where it crossed the frame. Might work for you.

massarosareloud

Well, made some serious progress this weekend. I managed to separate the exhaust pipe from the muffler, and rotated it to get it off the track bar, making it perpendicular to the ground. But in the process I found out that the manifold is 2.75" OD, which then connects to the cat which is 2.5" and that conversion is where the clamp is. So I am going to remove that and install a coupler, to get rid of the loudness. The loudness was caused because there wasn't a perfect seal between the manifold pipe and the cat. Unfortunately there was a coupler at one time, which has been broken off, but pieces still remain on the manifold so I need to take a grinding wheel to it.

Coming out of the cat is 2.25", and then out of the muffler is 2". Which I think is ridiculous that there isn't one consistent size between the exhaust components.

In the process I broke one half of the cat's heat shield off, but I am going to replace that this weekend.