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Muffler rattling diagnosis

7K views 39 replies 9 participants last post by  Godron629 
#1 ·
Hi Guys,

I have a stock 2003 Astro Cargo Van. When I accelerate from a stop (especially turning) I can hear something rattling from the rear end. A friend thought it was the diff, but I can make it happen by revving slightly in Drive slightly moving.

Shaking the exhaust with my hand, it sounds like something inside of the muffler is hitting the inside walls. It does not seem to hitting anything anywhere along the entire exhaust.

Has anyone had this before?

Do I need to replace the exhaust hanger insulators?

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#29 ·
Godron629 said:
I put my hand on the muffler (can, as I have called it) and :bouncy: it rattled hard along with the sound, and only when the sound could be heard.

So, I think there is almost certainly something inside of it that is loose or from upstream. I am not sure if this is a satisfactory conclusion, yet, but I am happy it is rattling and not grinding.
I bet if you held the muffler still, and moved only the tailpipe, you'd get your noise.

did I mention anywhere that I ran an exhaust shop for 12 years? I musta forgot to.
 
#31 ·
I was editing and trying to keep up with your replies. I screwed up the quote while you were posting it, so I edited my second reply. fun with forums!

nice drawing! I should print that & put it on my fridge :rolling:
the green arrows. but just gentle, not like wrestling a gator.
it might be the inlet tube, but I'm pretty sure it's the outlet.

I was happy to be of help, this forum has always been there for me.

if it matters, I think you did an excellent job of keeping us up to speed. you really wanted to find that noise, Buffalo Bill, and I would have too. I'm sure I'm not the only one who appreciates your sense of humor...there's always room for one more in chat :thumbup:
 
#32 ·
MechBob said:
oh,your ramps are fine,also.
Yeah, Bob, but you are not under them. Rhino Ramps and the Max version have a REAL BAD rep.
An easy search and read.

Rhino ramp 10.jpg
OMG - there are a lot of pics of these $50 ramp POSs
And you paid $100...?

...The company that made Rhino ramps several years ago went into bankruptcy partly due to claims regarding product liability.

Here are the "old school "Heavy Metal" ramps I was referring to.
I have seen "New" metal ramps that 'look' ok, but the steel is a much lighter gauge.
These yellow ramps weigh easily 30lbs each and have been around for 2 generations.

I am the 3rd owner:

2-2 06 Ramps for Randys Ramps.JPG
One bummer is that low front overhangs require a ramp for a ramp.

We also use Stands and 4x4 Cribbing if needed. Nice to have around for confidence.
 
#34 ·
about the rhino MAX ramps...I trimmed all the excess material off the bottoms, there were some big gobs that interfered with a flat seating, which I can guess would lead to splitting and failure.
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stock photo, not "max" & not mine, which I trimmed before 1st use.

note: I still set jack stands after the van's on the ramps.
 
#35 ·
I'll look into getting some metal ramps. (I do however have jackstands underneath! :pray: )

There is a guy around where I live that perpetually has a VW Jetta on 4 metal ramps and I am jealous. I have no jack, yet - historically most of my substantial maintenance takes place 4 hours away in a stocked garage, but that's getting old.

They were on sale for $50 CAD at princess auto, but I missed the sale - figured I'd just get them anyways, I was there for something else.
 
#36 ·
augidog said:
about the rhino MAX ramps...I trimmed all the excess material off the bottoms, there were some big gobs that interfered with a flat seating, which I can guess would lead to splitting and failure.stock photo, not "max" & not mine, which I trimmed before 1st use.

note: I still set jack stands after the van's on the ramps.
Same procedure here. Sweep drive way to get small rocks and sticks off. Drive van on ramps, put stands underneath and then work on it.
 
#38 ·
I have a set of the heavy yellow metal ramps that I got ~30 years ago at pep boys in Dover, DE. Those things don't care what I drive up on them, they've never flinched.

I did, however, when one dropped on my big toe while I was standing on concrete. Broke it through and through just below the nail (you can still feel the ridge). That didn't feel good, but I did complete the oil change on my roommate's car before going to the ER.
 
#39 ·
I have the same problem with my 97 Safari Van. The exhaust makes some rattling noises when the engine is cold. After about 90 seconds the noise goes completely away. I have been thinking about pulling the entire muffler off and blowing it out with my backpack blower to see what comes out. The last time I took a muffler off a vehicle I found half of a turbocharger wedged inside the muffler. I couldnt hear anything unusual on that vehicle, the two stroke diesel cannot be tamed to reasonable noise levels.

Chris
 
#40 ·
Rattling was starting to get on my nerves and was pretty constant when stopped in Drive, so I got the stocker replaced.

Van sounded like it was metallically (Metallica! :rockon:) purring in traffic.

Dynamax Super Turbo - Offset (Short version)

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Not super loud, but it's not welded and has a more standard aftermarket offset/length/diameter so I change it myself if I so desire. Shop diagnosis was the same as it was here, loose/broken baffle rattling.
 
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