Hey folks,

Things are going sweet in my new (to me) Jeep. The guy I bought it off
just had a new cat back Dynamax installed.

Over every bump comes the rattle/clunk from the rear. On some
startups, there is a clunk sounding like the exhaist hitting the floor
dead center of the Jeep.

Now I jumped under there and noticed the tailpipe is hitting / rubbing
the rear leaf, and the section that goes over the axle is about a half
inch from the floor of the Jeep.

The clearance is very, very tight between the leaf and the gas tank
skid plate. (1/2" on either side)

My question is:

Is it kosher to fabricate a rubber "donut" of sorts to act as a buffer
between the pipe and the leaf and the pipe and the floor. How hot does
that pipe get?

Do they sell "lowering" rubber hangers? The very end of the tailpipe
has a metal hanger supporting a metal support rod off the pipe...
leading to the never ending metal on metal squeak that I remedied by
slipping a rubber tube over the rod...but why the hell would they have
metal on metal with a moving part?!?!


Thanks,

~Jon

my stats:
91 YJ 4.0 auto
shackles giving about 1.5" lift

Jon wrote:
hot enough to melt a rubber donut. Concentrate on the hangers and get
them aligned properly.

The rubber isolator fell out when they did the cat-back and never got
put back in. They make several types. A local muffler shop will have
plenty and might even have a hanger they can thow in for you. If not,
the "help" section in pepboys or autozone will have the isolator.

--
DougW

"Jon" <campingisgood (AT) gmail (DOT) com> wrote

Take it to a muffler shop you can trust, and let them cure your headache for
you.
It'll be worth it not to have to screw with an exhaust rattle in your
driveway, on your back.
Like Doug said, they should have the correct hanger isolator in stock, and
it should be pretty cheap too.

Spdloader

Thanks for the heads-up fellas!

The rattle is driving me batty. I'll pull into the muffler guy and
have him take a look-see this weekend.



~Jon

It is supposed to be rubber mounted all the way back with the tailpipe
coming out at the corner on a 45 degree angle to the sides and back for
fume control.

I simply went and bought generic hangers to do mine when the 'muffler'
shop couldn't figure out how to install a Dynomax muffler into a CJ7
because CJ's here in Canada don't need cats and their book is American.

They just couldn't figure out how to let the main pipe run perfectly
'straight', it had to have a bend and flange.

Talk about losers calling themselves 'techs' not knowing shit if the
'computer' don't tell em so.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)


Jon wrote:

Hello Mike,

Well whoever installed it has the tail pipe shooting straight out the
back right between the gas tank skid plate and the rear passenger side
leaf spring - leading to metal on metal squeak, and the pipe banging
around over what seems to be just any imperfection in the road. It
does not extend beyond the bumper, but tucked neatly and tightly in
there.

To be perfectly honest, I'm not too interested in dropping it off
somewhere and ponying up an hourly rate for something I could just do
myself. Then again, I'm not really a mechanically inclined
individual.... yet.

The last thing was a stiff steering issue, and had a referred mechanic
fiddle with / troubleshoot the steering shaft & gearbox, only to
discover it was a bad PS pump like I originally said to him. He went
ahead and replaced it seeing that "he already had it off", soaked the
engine compartment with PS fluid in the process, then washed it down
with Kerosene, and now the TPS is giving me problems (code #24 / check
engine light).

Of course he claims it has nothing to do with what he did, or that the
fact that the steering wheel isn't quite perfectly straight is "no
biggie". The fact that the steering now doesn't return to center and
the engine almost conks out during idle when the peddle is tapped or
on highway acceleration (TPS thing) is met with the classic "it was
like that when it came in" ... like I'm some sort of idiot. I really
don't feel like playing slap & tickle with the guy since there's no
way to prove anything at this point. Plus, when my bullshit meter
starts pegging, I have no restraint or common sense - I just see red.

I'm just already tired of dealing with "mechanic$". I truly believe
they will "set things in motion" whenever they get the chance, and
play Mr. Nice Guy so you return to their shop.

Sorry for the diatribe, I'm just somewhat frustrated by all this
nonsense.



~Jon

The tailpipe should be coming out on a 45 between the tire and the
shackle on top of the spring. You can hang it off the frame there with
a universal hanger. I just bent the metal band of the hanger into a U
shape and hung it over the frame tight. There was a tab bolted to the
frame there at one point that was the hanger mount. I believe YJ's are
the same that way as the CJ's, just on the other side.

If it is straight out the back, the exhaust will vortex there and get in
through zippers or the slightest soft top crack and smell bad besides
being a CO risk. Out the side will vortex under the tire and come in
under the vehicle if there are any leaks.

Mike



Jon wrote:

I don't remember if the OP's Jeep was a CJ or YJ, but both the OEM
exhaust and the Gibson I have in my '93 exit between the gas tank skid
and passenger side shackle, the OEM angled downward, the Gibson straight
out.
It's a tight fit - when I first put the Gibson in, I broke the rearmost
hanger waaaayy up on the frame. I couldn't fix it right away, so I
drove around with the most god awful clanking for a while.

What you're describing sounds like the banging I had - check the hanger
all the way in the back, it attaches basically out the end of the tailpipe.

Mike Romain wrote:

That downward deflection is important. If that is all the YJ has, it's
easy to get an add on end piece shaped right.

Mike

The Merg wrote:

On 12 abr, 18:16, Mike Romain <roma... (AT) sympatico (DOT) ca> wrote:
My '95 went without the rearmost hanger for some time with no
clanking. You may want to check if the support that attaches by the
transmission (over the skid plate) is attached. If it is not, it may
be letting things move around.